David Jackson

USA TODAY

YOUNGSTOWN, Ohio — Likening the fight against terrorism to the Cold War and the battle against Nazism, Donald Trump pledged Monday to tighten restrictions on immigration from Muslim countries and assess allies based on their commitment to defeat "radical Islam."

"All actions should be oriented around this goal, and any country which shares this goal will be our ally," Trump said in what aides billed as a major foreign policy address. "Very important — some don't share this goal. We cannot always choose our friends but we can never fail to recognize our enemies."

The Republican nominee declared his opposition to "nation building" and other efforts to spread democracy in the Middle East, attacking the Obama administration — particularly former secretary of State Hillary Clinton — for policies toward nations like Iraq, Iran, Libya, Syria and Egypt.

Trump also blamed President Obama and Clinton for the rise of the Islamic State, the Middle-East-based extremist group also known as ISIS.

"The Obama-Clinton foreign policy has unleashed ISIS, destabilized the Middle East, and put the nation of Iran — which chants, 'death to America' — in a dominant position," Trump told an invited audience gathered at Youngstown State University in Ohio, a key state in his election battle against his Democratic opponent in November.

He also said Clinton "lacks the mental and physical stamina to take on ISIS and all of the many adversaries we face."

In his prepared speech, Trump advocated a foreign policy overhaul in three general areas: Diplomacy, immigration, and national security (particularly cyber-security).

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On the diplomatic front, Trump made a specific pledge to work with any country willing to make a commitment to help defeat "radical Islamic terrorism," and criticized Obama and Clinton for their reluctance to use that term.

That list of anti-ISIS allies would include Russia. As he has previously, Trump proposed a closer relationship with Russia in order to fight the Islamic State, telling the crowd, "Wouldn't that be a good thing?" Trump's critics say Russian President Vladimir Putin wants to use the Republican nominee to further an anti-Western agenda.

Various officials have also accused Russia and China of involvement in anti-U.S. cyber attacks.

Many of the things Trump attacked — including the Iraq invasion, the Libya intervention and the Iraq withdrawal under Obama — are developments he has expressed support for in past years. Trump also backed tactics Obama is already using, including drone strikes and targeting the leaders of terrorist groups.

Immigration has fueled much of Trump's presidential campaign, including his call for a wall along the U.S.-Mexico border. In his counter-terrorism speech, Trump re-asserted his call for a ban on immigrants from countries with a "history of exporting terrorism," saying it is impossible to properly vet people coming from those places.

Under Trump's plan, immigrants would also be subjected to tests to show a commitment to U.S. values, including religious freedom and tolerance.

Advocating "a new screening test for the threats we face today," Trump said that "I call it extreme vetting ... extreme, extreme vetting."

Senate Democratic leader Harry Reid mocked Trump over his call for an immigration test, saying the New York businessman should take it himself. "He would almost certainly fail, given his general ignorance and weak grasp of basic facts about American history, principles and functioning of our government," Reid said.

The foreign policy speech is a complement to the economy speech that Trump gave last week, aides said, describing them as twin pillars of the candidate's policy agenda.

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Trump's efforts to focus on the economy last week ran afoul following off-the-cuff comments he made at rallies. Critics jumped on Trump's statement that "Second Amendment people" might have to deal with the prospect of a Clinton presidency, calling it an incitement to violence.

The Republican nominee also described President Obama as a "founder" of the Islamic State last week, drawing criticism.

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The Clinton campaign said these and other comments show that Trump lacks the temperament to be president.

"Over the course of the campaign, Trump has put forth one falsehood after the next, trash-talking America and our leaders with ridiculous smears and using outrageous lies to stoke fears and division for personal gain," the Clinton campaign said in a pre-speech statement.

The Clinton campaign also called on Trump to disclose ties between campaign manager Paul Manafort and what it called "pro-Kremlin elements in Ukraine."

Campaigning with Clinton in Pennsylvania on Monday, Vice President Biden said that "Trump is already making our country less safe" by alienating Muslim allies and inflaming anti-American sentiment.

Clinton has also rolled out a counter-terrorism plan, arguing that allies would be more willing to work with her administration than one led by Trump. In addition to calling for improved cybersecurity, Clinton has proposed intensifying a coalition air campaign against ISIS and providing more support for partners engaged in ground operations.

In introducing Trump to the audience at Youngstown State, former New York City mayor Rudy Giuliani said the GOP nominee is "our only hope for change" when it comes to dealing with "the danger that we face from radical Islamic terrorism."

Trump running mate Mike Pence, who also spoke, said the real estate mogul offers "a new vision for a new time."