LONDON (Reuters) - Donald Trump’s first major foreign policy address alarmed American allies, who view the Republican front runner’s repeated invocation of an “America first” agenda as a threat to retreat from the world.

While most governments were careful not to comment publicly on a speech by a U.S. presidential candidate, Germany’s foreign minister veered from that protocol to express concern at Trump’s wording.

“I can only hope that the election campaign in the USA does not lack the perception of reality,” Frank-Walter Steinmeier said.

“The world’s security architecture has changed and it is no longer based on two pillars alone. It cannot be conducted unilaterally,” he said of foreign policy in a post-Cold War world. “No American president can get round this change in the international security architecture.... ‘America first’ is actually no answer to that.”

Carl Bildt, a former Swedish prime minister and foreign minister who served as UN envoy to the Balkans in the aftermath of the Yugoslav wars of the 1990s, said he heard Trump’s speech as “abandoning both democratic allies and democratic values”.

“Trump had not a word against Russian aggression in Ukraine, but plenty against past U.S. support for democracy in Egypt,” Bildt said on Twitter, referring to lines from Trump’s speech that criticized the Barack Obama administration for withdrawing support for autocrat Hosni Mubarak during a 2011 uprising.

“FIRST ISOLATIONIST CANDIDATE”

Trump’s speech, uncharacteristically read out from a teleprompter, seemed aimed at showing a more serious side of a politician who has said he intends to act more “presidential” after months of speaking mainly off the cuff.

He promised “a disciplined, deliberate and consistent foreign policy” in contrast to the “reckless, rudderless and aimless” policies of Obama and former Secretary of State Hillary Clinton, Trump’s likely Democratic opponent if he secures the Republican nomination.

The speech included no dramatic new policy proposals that might generate headlines, such as his past calls to bar Muslims from entering the United States or to build a wall on the frontier with Mexico.

Where he was specific, like rejecting the terms of last year’s nuclear deal with Iran, calling for more investment in missile defense in Europe and accusing the Obama administration of tepid support for Israel, he was firmly within the Republican mainstream.

A major theme -- that more NATO allies should spend at least 2 percent of their economic output on defense -- is one that has also been taken up by the Obama administration itself, including repeatedly during the president’s visit to Europe last week.

Nevertheless, Trump’s rhetoric raised alarm in allied countries that still rely on the superpower for defense, particularly the phrase “America first”, used in the 1930s by isolationists that sought to keep the United States out of World War Two.

Former South Korean Vice Foreign Minister Kim Sung-han, who now teaches at the Korea University in Seoul, said Trump would be “the first isolationist to be U.S. presidential candidate, while in the post-war era all the U.S. presidents have been to varying degrees internationalists.”

“Saying the U.S. will no longer engage in anything that is a burden in terms of its relationships with allies, it would be almost like abandoning those alliances,” he said. “It will inevitably give rise to anti-American sentiment worldwide.”

Xenia Wickett, head of the U.S. and Americas Programme at Britain’s Chatham House think tank, said the speech “suggests Trump would make America’s allies less secure rather than more.

“He talked about allies being confident but all of his rhetoric suggested that America should be unpredictable and that America’s allies needed to stand up for themselves.”

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“DISASTER”

Earlier in the U.S. nomination process, foreign leaders were not shy to condemn Trump openly and publicly.

In December, when Trump called for his temporary ban on admitting Muslims, British Prime Minister David Cameron called him “divisive, stupid and wrong”. Hundreds of thousands of Britons signed a petition calling for Trump to be banned from Britain for hate speech, which was taken up in parliament. Cameron declined to ban Trump, but said: “If he came to visit our country, I think he would unite us against him.”

In January, German Vice Chancellor Sigmar Gabriel lumped Trump together with the leaders of European far-right parties as “not only a threat to peace and social cohesion, but also to economic development”.

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These days, with Trump now seen as likely to win his party’s nomination, European officials are more circumspect in public, but sound no less alarmed in private.

A Trump presidency “would be a disaster for EU-U.S. ties,” said one senior EU official involved in shaping foreign policy in Brussels.

“Right now, we and the Obama administration generally understand each other. I don’t think we understand Donald Trump. He has no understanding of the delicate, complex nature of foreign policy on Europe’s doorstep.”

Nevertheless, some of the policies Trump shares with other Republicans do have sympathetic audiences abroad.

Ryszard Terlecki, head of the parliamentary group of Poland’s ruling rightwing Law and Justice party, said Trump had a point when criticizing the Obama administration for backing away from plans for increased missile defense.

“This decision influenced very badly the security of this part of Europe. If it weren’t for that, the conflict in Ukraine would not escalate,” he told Reuters.

Israeli Prime Minister Benjamin Netanyahu has strongly opposed the Obama administration’s deal with Iran, and Trump’s speech, like an earlier one to a pro-Israel lobby group in Washington, went down well with some right-leaning Israelis.

“Trump wants an America that is decent, strong, loyal - but also no patsy. And he sees in Israel the most loyal ally of the U.S.” wrote Boaz Bismuth, diplomatic correspondent for the pro-Netanyahu daily Israel Hayom.

In the Arab world, where governments and their citizens are also alarmed at the rise of non-Arab Iran, Trump’s strong rejection of the deal with Tehran is a popular position that would have been embraced if expressed by another candidate.

But Trump’s previous call to ban Muslims from the United States has made him anathema in the region. Emirati political analyst Abdulkhaleq Abdullah said no speech would be enough to salvage his reputation there: “He’s a racist and a chauvinist who will never be widely welcomed in the Arab world.”

Or, as Kuwaiti twitter user Mohammed al-Ammar wrote: “Some of his speech is correct and logical, but the problem is, he’s still #Trump.”