Fact-Checking Donald Trump's Foreign Policy Speech Ideological screening isn’t new, but using race or religion could pose problems.

 -- Donald Trump discussed foreign policy in a speech in Youngstown, Ohio, today. ABC News fact-checked several of his claims that touched on his policy proposals, his position on the Iraq War and President Barack Obama’s counterterrorism track record.

On Troop Withdrawal

Claim: President Barack Obama set the terms of U.S. troop withdrawal from Iraq.

Status: False. The withdrawal of U.S. forces from Iraq was established by President George W. Bush.

Trump said of Obama and then–Secretary of State Hillary Clinton, “They said, ‘We’re moving out. Here’s our time. Here’s our date.’ Who would do this but an incompetent president?”

Background: The timetable for the withdrawal of U.S. forces from Iraq was governed by an agreement signed in 2008 by Bush known as the U.S.-Iraq Status of Forces Agreement, or SOFA. Article 24 of the agreement reads, “All the United States forces shall withdraw from all Iraqi territory no later than Dec. 31, 2011.” So Trump’s claim is false.

The more difficult question is whether the Obama administration, with more effort, could have brokered an agreement that extended U.S. troop presence in Iraq. Obama announced in October of 2011 that U.S. troops would pull out of Iraq after talks about keeping a U.S. military presence in Iraq beyond 2011 collapsed.

Administration officials have claimed that Iraqi Prime Minister Nouri al-Maliki’s refusal to grant immunity to U.S. troops scuttled the possibility of reaching a new agreement. Yet some believe the administration was eager to deliver on its campaign promise to end the Iraq War, rather than commit to extending the U.S. troop presence there.

On Nation Building

Claim: The United States is in the era of nation building, which Trump will end.

Status: Mostly false. Obama has largely phased out the kind of large-scale nation-building efforts most closely associated with Bush’s tenure, when hundreds of thousands of U.S. troops were deployed to rebuild Iraq and Afghanistan.

Trump said, “If I become president, the era of nation building will be brought to a very swift and decisive end.”

Background: Trump’s comment appears to refer to the extensive U.S. effort to help rebuild Iraq and Afghanistan after the U.S. military’s offensives in both those nations, which began under the Bush administration. In tandem with the reconstruction efforts, the U.S. military also began counterinsurgency missions in each country that required large troop presences and greater interaction with local residents.

The Obama administration continued those programs as it reduced the number of U.S. troops in Iraq and Afghanistan. It also shifted to training missions in both countries and moved away from large unilateral U.S. military interventions toward working with international coalitions when it comes to regional crises.

The 2011 U.S. intervention in Libya reflected the Obama administration’s policy of working with international coalitions in hot spots around the world without having to send in ground troops.

The United States worked with a coalition of regional allies to conduct airstrikes that helped Libyan rebel forces battling forces supporting Libyan strongman Col. Muammar Gaddafi.

Earlier this year, Obama acknowledged in a Fox News interview that failing to prepare for the aftermath of Gaddafi’s overthrow was his biggest mistake while in office.

Asked about the worst mistake of his presidency, Obama replied, “Probably failing to plan for the day after, what I think was the right thing to do, in intervening in Libya.”

On Honor Killings

Claim: Many cases of honor killings have occurred in the United States.

Status: True. The Department of Justice last year commissioned a comprehensive study that estimated 23 to 27 honor killings occur every year in the U.S.

Background: A Department of Justice–commissioned study last year shed light on several startling findings about honor killings. This kind of violence is typified by an intent to repair or prevent further damage to a family’s honor and, according to the study, is “most prevalent among people from Islamic regions of the Middle East, North Africa and South Asia.”

Researchers estimate that 23 to 27 honor killings occur in the United States every year, according to Westat, the corporation that conducted the report. The study also found that in North America, fathers were involved 100 percent of the time when the victim was a daughter 18 or younger. Researchers also found that 91 percent of victims in North America were murdered for being “too Westernized.”

On the Iraq War

Claim: Trump opposed the Iraq War “from the beginning.”

Status: Questionable. The quote from the interview that Trump cited in his speech is not as clear as he described it and does not express opposition or support of a U.S. invasion of Iraq.

Trump said, “Three months before the invasion, I said in an interview with Neil Cavuto — to whom I offer my best wishes for a speedy recovery — that perhaps we shouldn’t be doing it yet. And that the economy is a much bigger problem.”

Background: In his speech, Trump referred to a Jan. 28, 2003, interview with Fox News’ Cavuto as proof that he opposed the war in Iraq before it began.

In the interview Cavuto asked Trump, “So you’re saying the leash on this is getting kind of short here, that the president has got to do something presumably sooner rather than later and stringing this along could ultimately hurt us.”

Trump’s full response was, “Well, he has either got to do something or not do something, perhaps, because perhaps shouldn’t be doing it yet and perhaps we should be waiting for the United Nations, you know. He’s under a lot of pressure. He’s — I think he’s doing a very good job. But of course, if you look at the polls, a lot of people are getting a little tired. I think the Iraqi situation is a problem. And I think the economy is a much bigger problem, as far as the president is concerned.”

In a 2002 interview with Howard Stern, Trump seemed to indicate he supported an invasion of Iraq.

“Yeah, I guess so,” Trump responded when asked by Stern if he supported an invasion. “I wish the first time it was done correctly.”

On Vetting Immigrants

Claim: Trump could use federal legal authority to implement his “extreme vetting” proposal.

Status: Unclear. While federal immigration law lets the president bar entry of aliens who would be detrimental to U.S. interests, legal scholars say such authority has never been used the way Trump has proposed.

Background: Under Trump’s newly announced policy of “extreme vetting,” immigrants who sympathize with terrorists, are hostile toward the United States or believe Sharia should supersede U.S. law would be blocked from entering the country.

Federal immigration law allows the president to suspend entry of aliens or categories of aliens who “would be detrimental to the interests of the United States,” legal scholars told ABC News.

But federal authority has never been used the way Trump has proposed, which could give rise to legal challenges.

“This authority has never been used in the way that Trump suggests, and it is so broad that the Supreme Court would likely subject it to some constitutional limitation,” Peter Schuck of Yale Law School said.

Ideological screening isn’t new, according to Akhil Amar of Yale Law School.

“We’ve always asked all sorts of questions about people’s beliefs, and people with un-American points of view will be screened out,” Amar said.

But legal issues could arise if the United States discriminates on the basis of race or religion, and Trump could face a separation of power challenge if his executive order is too broad, Amar said. Also, Trump’s “extreme vetting” may be unconstitutional if applied to U.S. citizens or permanent residents or others with legal rights to enter the country.

David Martin, a former Homeland Security official now at the University of Virginia Law School, said that while Trump’s proposal is probably legal, it is “inconsistent with our constitutional values.”

“We are not at a point where we should be engaging in this kind of sweeping inquisition of people who want to come to the U.S.,” Martin said.