I would like to thank Congress and the Congressional Institute for the invitation to be here today. The opportunity to visit the United States is always special. And to be invited to be the first serving head of government to address this important conference is an honor indeed.

I defy any person to travel to this great country at any time and not to be inspired by its promise and its example.

For more than two centuries, the very idea of America -- drawn from history and given written form in a small hall not far from here -- has lit up the world.

That idea -- that all are created equal and that all are born free -- has never been surpassed in the long history of political thought.

And it is here -- on the streets and in the halls of this great city of Philadelphia -- that the founding fathers first set it down, that the textbook of freedom was written, and that this great nation that grew "from sea to shining sea" was born.

Since that day, it has been America's destiny to bear the leadership of the free world and to carry that heavy responsibility on its shoulders. But my country, the United Kingdom of Great Britain and Northern Ireland, has been proud to share that burden and to walk alongside you at every stage.

For the past century, Britain and America -- and the unique and special relationship that exists between us -- have taken the idea conceived by those "56 rank-and-file, ordinary citizens," as President Reagan called them, forward. And because we have done so, time and again it is the relationship between us that has defined the modern world.

One hundred years ago this April, it was your intervention in the First World War that helped Britain, France, our friends in the Commonwealth and other allies to maintain freedom in Europe.

A little more than 75 years ago, you responded to the Japanese attack on Pearl Harbor by joining Britain in the Second World War and defeating fascism not just in the Pacific but in Africa and Europe, too.

And later, in the aftermath of these wars, our two countries led the West through the Cold War, confronting communism and ultimately defeating it not just through military might, but by winning the war of ideas. And by proving that open, liberal, democratic societies will always defeat those that are closed, coercive and cruel.

But the leadership provided by our two countries through the special relationship has done more than win wars and overcome adversity. It made the modern world.

The institutions upon which that world relies were so often conceived or inspired by our two nations working together.

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The United Nations -- in need of reform, but vital still -- has its foundations in the special relationship, from the original Declaration of St James' Palace to the Declaration by United Nations, signed in Washington, and drafted themselves by Winston Churchill and President Franklin D. Roosevelt.

The World Bank and International Monetary Fund, born in the postwar world at Bretton Woods, were conceived by our two nations working together.

And NATO -- the cornerstone of the West's defense -- was established on the bonds of trust and mutual interests that exist between us.

Some of these organizations are in need of reform and renewal to make them relevant to our needs today. But we should be proud of the role our two nations -- working in partnership -- played in bringing them into being, and in bringing peace and prosperity to billions of people as a result.

Because it is through our actions over many years, working together to defeat evil or to open up the world, that we have been able to fulfill the promise of those who first spoke of the special nature of the relationship between us. The promise of freedom, liberty and the rights of man.

"We must never cease," Churchill said, "to proclaim in fearless tones the great principles of freedom and the rights of man which are the joint inheritance of the English-speaking world and which through Magna Carta, the Bill of Rights, the Habeas Corpus, trial by jury, and the English common law, find their most famous expression in the American Declaration of Independence."

So it is my honor and privilege to stand before you today in this great city of Philadelphia to proclaim them again, to join hands as we pick up that mantle of leadership once more, to renew our special relationship and to recommit ourselves to the responsibility of leadership in the modern world.

Change in America

And it is my honor and privilege to do so at this time, as dawn breaks on a new era of American renewal.

For I speak you not just as Prime Minister of the United Kingdom, but as a fellow conservative who believes in the same principles that underpin the agenda of your party.

The value of liberty, the dignity of work, the principles of nationhood, family, economic prudence, patriotism, and putting power in the hands of the people. Principles instilled in me from a young age. Principles my parents taught me in the vicarage in southern England in which I was raised.

And I know it is these principles that you have put at the heart of your plan for government. And your victory in these elections gives you the opportunity to put them at the heart of this new era of American renewal, too.

President Trump's victory, achieved in defiance of all of the pundits and the polls, and rooted not in the corridors of Washington, but in the hopes and aspirations of working men and women across this land, you're part of his victory, in both the Congress and the Senate, where you swept all before you, secured with great effort, and achieved with an important message of national renewal.

And because of this, because of what you have done together, because of that great victory you have won, America can be stronger, greater, and more confident in the years ahead. And a newly emboldened, confident America is good for the world.

An America that is strong and prosperous at home is a nation that can lead abroad. But you cannot -- and should not -- do so alone. You have said that it is time for others to step up. And I agree.

Sovereign countries cannot outsource their security and prosperity to America. And they should not undermine the alliances that keep us strong by failing to step up and play their part.

This is something Britain has always understood. It is why Britain is the only country in the G-20 -- other than yours -- to meet its commitment to spend 2% of GDP on defense, and to invest 20% of that in upgrading equipment. It is why Britain is the only country in the G-20 to spend 0.7% of gross national income on overseas development. It is why my first act as Prime Minister last year was to lead the debate in Parliament that ensured the renewal of Britain's independent nuclear deterrent. And it is why the government I lead will increase spending on defense in every year of this Parliament.

It is why Britain is a leading member -- alongside the United States -- of the coalition working successfully to defeat Daesh; why we have agreed to send 800 troops to Estonia and Poland as part of NATO's forward presence in Eastern Europe; why we are increasing our troop contribution to NATO's Resolute Support mission that defends the Afghan government from terrorism; and it is why we are reinforcing our commitment to peacekeeping operations in Kosovo, South Sudan and Somalia.

And it is why Britain is leading the way in pioneering international efforts to crack down on modern slavery - one of the great scourges of our world - wherever it is found. I hope you will join us in that cause -- and I commend Sen. (Bob) Corker in particular for his work in this field. It is good to have met him here today.

As Americans know, the United Kingdom is by instinct and history a great, global nation that recognizes its responsibilities to the world.

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And as we end our membership of the European Union -- as the British people voted with determination and quiet resolve to do last year -- we have the opportunity to reassert our belief in a confident, sovereign and global Britain, ready to build relationships with old friends and new allies alike.

We will build a new partnership with our friends in Europe. We are not turning our back on them, or on the interests and the values that we share. It remains overwhelmingly in our interests -- and in those of the wider world -- that the EU should succeed. And for as long as we remain members we will continue to play our full part, just as we will continue to cooperate on security, foreign policy and trade once we have left.

But we have chosen a different future for our country.

A future that sees us restore our parliamentary sovereignty and national self-determination, and to become even more global and internationalist in action and in spirit.

A future that sees us take back control of the things that matter to us -- things like our national borders and immigration policy, and the way we decide and interpret our own laws -- so that we are able to shape a better, more prosperous future for the working men and women of Britain.

A future that sees us step up with confidence to a new, even more internationalist role, where we meet our responsibilities to our friends and allies, champion the international cooperation and partnerships that project our values around the world, and continue to act as one of the strongest and most forceful advocates for business, free markets and free trade anywhere around the globe.

This is a vision of a future that my country can unite around -- and that I hope your country, as our closest friend and ally, can welcome and support.

Renewed special relationship

So as we rediscover our confidence together -- as you renew your nation just as we renew ours -- we have the opportunity -- indeed the responsibility -- to renew the special relationship for this new age. We have the opportunity to lead, together, again.

Because the world is passing through a period of change -- and in response to that change we can either be passive bystanders, or we can take the opportunity once more to lead. And to lead together.

I believe it is in our national interest to do so. Because the world is increasingly marked by instability and threats that risk undermining our way of life and the very things that we hold dear.

The end of the Cold War did not give rise to a new world order. It did not herald the end of history. It did not lead to a new age of peace, prosperity and predictability in world affairs.

For some -- the citizens of Central and Eastern Europe in particular -- it brought new freedom.

But across the world, ancient ethnic, religious and national rivalries -- rivalries that had been frozen through the decades of the Cold War -- returned. New enemies of the West and our values -- in particular in the form of radical Islamists -- have emerged. And countries with little tradition of democracy, liberty and human rights -- notably China and Russia -- have grown more assertive in world affairs. The rise of the Asian economies -- China yes, but democratic allies like India, too -- is hugely welcome. Billions are being lifted out of poverty and new markets for our industries are opening up.

But these events -- coming as they have at the same time as the financial crisis and its fallout, as well as a loss of confidence in the West following 9/11, and difficult military interventions in Iraq and Afghanistan - have led many to fear that, in this century, we will experience the eclipse of the West.

But there is nothing inevitable about that. Other countries may grow stronger. Big, populous countries may grow richer. And as they do so, they may start to embrace more fully our values of democracy and liberty.

But even if they do not, our interests will remain. Our values will endure. And the need to defend them and project them will be as important as ever.

So we -- our two countries together -- have a responsibility to lead. Because when others step up as we step back, it is bad for America, for Britain and the world.

It is in our interests -- those of Britain and America together -- to stand strong together to defend our values, our interests and the very ideas in which we believe.

This cannot mean a return to the failed policies of the past. The days of Britain and America intervening in sovereign countries in an attempt to remake the world in our own image are over. But nor can we afford to stand idly by when the threat is real and when it is in our own interests to intervene. We must be strong, smart and hard-headed. And we must demonstrate the resolve necessary to stand up for our interests.

And whether it is the security of Israel in the Middle East or the Baltic states in Eastern Europe, we must always stand up for our friends and allies in democratic countries that find themselves in tough neighborhoods, too.

We each have different political traditions. We will sometimes pursue different domestic policies. And there may be occasions on which we disagree. But the common values and interests that bring us together are hugely powerful.

And -- as your foremost friend and ally -- we support many of the priorities your government has laid out for America's engagement with the world.

It is why I join you in your determination to take on and defeat Daesh and the ideology of Islamist extremism that inspires them and many others terrorist groups in the world today. It is in both our national interests to do so. This will require us to use the intelligence provided by the finest security agencies in the world. And it will require the use of military might.

But it also demands a wider effort. Because one of the lessons of fighting terrorism in the last 15 years or so is yes, killing terrorists can save innocent lives. But until we kill the idea that drives them, the ideology, we will always have to live with this threat.

And as they are defeated on the ground, the terrorists are exploiting the internet and social media to spread this ideology that is preying on vulnerable citizens in our own countries, inspiring them to commit acts of terror in our own cities.

That is why the UK has led the world in developing a strategy for preventing violent extremism, and why the British and American governments are working together to take on and defeat the ideology of Islamist Extremism. I look forward to working with the President and his Administration to step up our efforts still further in order to defeat this evil ideology.

But of course, we should always be careful to distinguish between this extreme and hateful ideology, and the peaceful religion of Islam and the hundreds of millions of its adherents - including millions of our own citizens and those further afield who are so often the first victims of this ideology's terror. And nor is it enough merely to focus on violent extremism. We need to address the whole spectrum of extremism, starting with the bigotry and hatred that can so often turn to violence.

Yet ultimately to defeat Daesh, we must employ all of the diplomatic means at our disposal. That means working internationally to secure a political solution in Syria and challenging the alliance between the Syrian regime and its backers in Tehran.

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When it comes to Russia, as so often it is wise to turn to the example of President Reagan who -- during his negotiations with his opposite number Mikhail Gorbachev -- used to abide by the adage "trust but verify". With President Putin, my advice is to "engage but beware."

There is nothing inevitable about conflict between Russia and the West. And nothing unavoidable about retreating to the days of the Cold War. But we should engage with Russia from a position of strength. And we should build the relationships, systems and processes that make cooperation more likely than conflict -- and that, particularly after the illegal annexation of Crimea, give assurance to Russia's neighboring states that their security is not in question. We should not jeopardize the freedoms that President Reagan and Mrs. Thatcher brought to Eastern Europe by accepting President Putin's claim that it is now in his sphere of influence.

And progress on this issue would also help to secure another of this nation's priorities -- to reduce Iran's malign influence in the Middle East.

This is a priority for the UK too as we support our allies in the Gulf States to push back against Iran's aggressive efforts to build an arc of influence from Tehran through to the Mediterranean.

The nuclear deal with Iran was controversial. But it has neutralized the possibility of the Iranians acquiring nuclear weapons for more than a decade. It has seen Iran remove 13,000 centrifuges together with associated infrastructure and eliminate its stock of 20% enriched uranium. That was vitally important for regional security. But the agreement must now be very carefully and rigorously policed -- and any breaches should be dealt with firmly and immediately.

Strong institutions and nations

To deal with the threats of the modern world, we need to rebuild confidence in the institutions upon which we all rely.

In part that means multinational institutions. Because we know that so many of the threats we face today -- global terrorism, climate change, organized crime, unprecedented mass movements of people -- do not respect national borders. So we must turn towards those multinational institutions like the UN and NATO that encourage international cooperation and partnership.

But those multinational institutions need to work for the countries that formed them, and to serve the needs and interests of the people of those nations. They have no democratic mandate of their own. So I share your reform agenda and believe that, by working together, we can make those institutions more relevant and purposeful than they are today.

I call on others, therefore, to join us in that effort and to ensure they step up and contribute as they should. That is why I have encouraged Antonio Guterres, the new UN Secretary General, to pursue an ambitious reform program, focusing the United Nations on its core functions of peacekeeping, conflict prevention and resolution. And it is why I have already raised with my fellow European leaders the need to deliver on their commitments to spend 2% of their GDP on defense -- and 20% of their defense budgets on equipment.

It is also why I have already raised with Jens Stoltenberg -- the Secretary General of NATO -- the need to make sure the Alliance is as equipped to fight terrorism and cyber warfare, as it is to fight more conventional forms of war.

America's leadership role in NATO -- supported by Britain -- must be the central element around which the Alliance is built. But alongside this continued commitment, I am also clear that EU nations must similarly step up to ensure this institution that provides the cornerstone of the West's defense continues to be as effective as it can be.

Yet the most important institution is -- and should always be -- the nation state. Strong nations form strong institutions. And they form the basis of the international partnerships and cooperation that bring stability to our world.

Nations, accountable to their populations -- "deriving" as the Declaration of Independence puts it "their just powers from the consent of the governed" -- can choose to join international organizations, or not. They can choose to cooperate with others, or not. Choose to trade with others, or not.

Which is why if the countries of the European Union wish to integrate further, my view is that they should be free to do so. Because that is what they choose.

But Britain -- as a sovereign nation with the same values but a different political and cultural history -- has chosen to take a different path.

Because our history and culture is profoundly internationalist.

We are a European country -- and proud of our shared European heritage -- but we are also a country that has always looked beyond Europe to the wider world. We have ties of family, kinship and history to countries like India, Pakistan, Bangladesh, Australia, Canada, New Zealand, and countries across Africa, the Pacific and Caribbean.

And of course, we have ties of kinship, language and culture to these United States too. As Churchill put it, we "speak the same language, kneel at the same altars and, to a very large extent, pursue the same ideals".

And, today, increasingly we have strong economic, commercial, defense and political relationships as well.

So I am delighted that the new Administration has made a trade agreement between our countries one of its earliest priorities. A new trade deal between Britain and America must work for both sides and serve both of our national interests. It must help to grow our respective economies and to provide the high-skilled, high-paid jobs of the future for working people across America and across the UK.

And it must work for those who have too often felt left behind by the forces of globalization. People, often those on modest incomes living in relatively rich countries like our own, who feel that the global system of free markets and free trade is simply not working for them in its current form.

Such a deal -- allied to the reforms we are making to our own economy to ensure wealth and opportunity is spread across our land -- can demonstrate to those who feel locked out and left behind that free markets, free economies and free trade can deliver the brighter future they need. And it can maintain -- indeed it can build -- support for the rules-based international system on which the stability of our world continues to rely.

The UK is already America's fifth largest export destination, while your markets account for almost a fifth of global exports from our shores. Exports to the UK from this State of Pennsylvania alone account for more than $2 billion a year. The UK is the largest market in the EU -- and the third largest market in the world -- for exporters here.

America is the largest single destination for UK outward investment and the single largest investor in the UK. And your companies are investing or expanding in the UK at the rate of more than ten projects a week.

British companies employ people in every US state from Texas to Vermont. And the UK-US Defense relationship is the broadest, deepest and most advanced of any two countries, sharing military hardware and expertise. And of course, we have recently invested in the new F-35 strike aircraft for our new aircraft carriers that will secure our naval presence -- and increase our ability to project our power around the world -- for years to come.

Because of these strong economic and commercial links -- and our shared history and the strength of our relationship -- I look forward to pursuing talks with President Trump and his new Administration about a new UK/US Free Trade Agreement in the coming months. It will take detailed work, but we welcome your openness to those discussions and hope we can make progress so that the new, Global Britain that emerges after Brexit is even better equipped to take its place confidently in the world.

We can build a better future

Such an agreement would see us taking that next step in the special relationship that exists between us. Cementing and affirming one of the greatest forces for progress this world has ever known.

Seventy years ago in 1946, Churchill proposed a new phase in this relationship -- to win a Cold War that many had not even realized had started. He described how an iron curtain had fallen from the Baltic to the Adriatic, covering all the capitals of the ancient states of Central and Eastern Europe: Warsaw, Berlin, Prague, Vienna, Budapest, Belgrade, Sofia and Bucharest.

Today those great cities -- homes of great culture and heritage -- live in freedom and peace. And they do so because of the leadership of Britain and America, and of Mrs. Thatcher and President Reagan.

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They do so -- ultimately -- because our ideas will always prevail.

And they do so because, when the world demands leadership, it is this alliance of values and interests -- this Special Relationship between two countries -- that, to borrow the words of another great American statesman, enters the arena, with our faces marred by dust and sweat and blood, to strive valiantly and know the triumph of high achievement.

As we renew the promise of our nations to make them stronger at home -- in the words of President Reagan as the "sleeping giant stirs" -- so let us renew the relationship that can lead the world towards the promise of freedom and prosperity marked out in parchment by those ordinary citizens 240 years ago.

So that we may not be counted with the "cold and timid souls who know neither victory or defeat", but with those who "strive to do the deeds" that will lead us to a better world.

That better future is within reach. Together, we can build it.