David Jackson

USA TODAY

Apparently following through on his pledge of aggressive foreign policy, President Trump has used his first two weeks in office to put Iran "on notice" from the United States, shut down refugee programs, and engage in reportedly contentious, sometimes threatening telephone calls with leaders of two U.S. allies: Australia and Mexico.

Trump's national security adviser announced the notice on Iran on Wednesday over a reported missile launch, while leaked documents reflected the calls between Trump and the presidents of Mexico and Australia over the fraught issues of drug trafficking, immigration and refugees.

Speaking at the annual National Prayer Breakfast on Thursday, Trump told people they shouldn't worry about his "tough phone calls," and the country needs to be "a little tough" in meeting global challenges.

"We're (being) taken advantage of by every nation in the world, virtually," the president said. "It's not going to happen anymore."

Later, at the White House, Trump told reporters that "we have some wonderful allies, and we're going to keep it that way — but we need to be treated fairly also."

A Trump dust-up with Australian Prime Minister Malcolm Turnbull over refugees prompted a remarkable response from U.S. Sen. John McCain, R-Ariz., who said he called the Australian ambassador to the United States "to express my unwavering support for the U.S.-Australia alliance" and "convey to the people of Australia that their American brothers and sisters value our historic alliance."

Trump's aggressive moves echo comments he made during the campaign in criticizing various trade deals, defending his new travel ban from seven Muslim-majority countries and confronting Iran about missile tests.

"Iran has been formally PUT ON NOTICE for firing a ballistic missile.Should have been thankful for the terrible deal the U.S. made with them!" Trump tweeted earlier in the day, referring to the nuclear deal with Tehran signed by the Obama administration. Michael Flynn, the retired Army lieutenant general who is Trump's national security adviser, sent Iran the same message Wednesday.

Under the agreement, the United States and allies reduced sanctions on Iran as it gave up paths to construction of nuclear weapons.

Having threatened to cancel that deal during his presidential campaign, Trump also tweeted that "Iran was on its last legs and ready to collapse until the U.S. came along and gave it a life-line in the form of the Iran Deal: $150 billion."

Asked Thursday if military action is "off the table" with respect to Iran, Trump gave a standard response: "Nothing's off the table."

Trump, who pledged an "America First" foreign policy during his campaign, also said he is reviewing another diplomatic agreement, one with Australia in which the United States would take 1,250 refugees being held in an Australian detention center.

"Do you believe it?" Trump tweeted. "The Obama Administration agreed to take thousands of illegal immigrants from Australia. Why? I will study this dumb deal!"

Trump spoke out after reports of a tense phone call Saturday between Trump and Australian Prime Minister Turnbull.

The Washington Post reported that Trump "blasted" Turnbull about the refugee agreement and "boasted about the magnitude of his electoral college win, according to senior U.S. officials briefed on the Saturday exchange. Then, 25 minutes into what was expected to be an hour-long call, Trump abruptly ended it." The phone call took place Saturday, a day after Trump signed an order barring entry into the United States to travelers from seven Muslim-majority nations.

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Calling the agreement with Australia "the worst deal ever," Trump told Turnbull that "he was 'going to get killed' politically and accused Australia of seeking to export the 'next Boston bombers,'" the Post reported.

Many of the refugees involved in the U.S.-Australia agreement are from Iran, Iraq, Somalia and Sudan — countries that are on the banned list issued by the Trump administration last week.

During a meeting with business people at the White House, Trump said that "I love Australia as a county," but he is upset about its refugee deal with the Obama administration and is reviewing it.

"We'll see what happens," he said.

On another diplomatic front, the Associated Press reported that Trump told Mexico President Enrique Peña Nieto in their phone call that he might send U.S. troops into the country because of its gang problem.

"You have a bunch of bad hombres down there," Trump told Peña Nieto, according an excerpt of the call given to AP. "You aren't doing enough to stop them. I think your military is scared. Our military isn't, so I just might send them down to take care of it."

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Both nations have denied the report.

Eduardo Sanchez, spokesman for Mexico's presidential office, told Radio Formula: "It is absolutely false that the president of the United States threatened to send troops to Mexico."

The White House put out a statement saying that "reports that the President threatened to invade Mexico are false" and that the two leaders had a constructive conversation.

It confirmed the "hombre" quote but said it was made in jest.

"The comments in question, while lighthearted, were part of a discussion about how the United States and Mexico could work collaboratively to combat drug cartels and other criminal elements, and make the border more secure," the statement said. "These are areas of agreement between our two countries."

During the call and in statements afterward, Trump reiterated his plans to have a wall built along the United States' southern border that Mexico would pay for; Mexico's government said it will never finance such a project.

All of this tookplace as Secretary of State Rex Tillerson had his first day at the State Department, having been confirmed by the Senate and sworn in Wednesday.

Some analysts questioned how effective Trump's get-tough policies will be in real life.

Mehrzad Bourujerdi, a political science professor at Syracuse University who specializes in Iranian and Middle Eastern politics, said Trump's team has yet to formulate a coherent Iran policy. Bourujerdi said that "muscular tweets and orations will not intimidate an Iranian leadership that has dealt with five other American presidents over the last 38 years."

Critics noted that Trump's aggressive attitude has an exception: Russia. Democrats say Trump and his team have too cozy a relationship with Russian President Vladimir Putin, despite evidence that it interfered in last year's election by hacking Democratic emails.

Senate Minority Leader Chuck Schumer, D-N.Y., said that "in addition to dealing with the fallout from the president's first engagements with Australia and Mexico," Tillerson and his State Department have to address new Russian military aggression in Ukraine.

"Russia remains a big threat to our nation, and countering them needs to remain a deeply bipartisan effort," Schumer said.

Trump repeatedly vowed "America First" during the campaign, and more changes could be on the way. Aides said the administration is reviewing its financial commitments to the United Nations and related agencies, as well as a variety of multinational agreements.