Anti-Trump demonstrators dressed as a wall gather at the main entrance of the Quicken Loans Arena on the third day of the Republican National Convention in Cleveland, Ohio on July 20, 2016. (Jabin Botsford/The Washington Post)

First Donald Trump said that he wanted to block nearly all foreign Muslims from entering the United States. More recently, he decided to stop using the word "Muslim" as he called for halting immigration from countries with high rates of terrorism, although he has yet to say which countries that would include.

At a rally in Portland, Maine, on Thursday afternoon, Trump provided a lengthy explanation of why he thinks the United States needs to be skeptical of immigrants from many countries, even if they follow the legal process. Reading from notes, Trump listed nearly a dozen examples of immigrants, refugees or students who came to the United States legally -- often applying for and receiving citizenship -- and then plotted to kill Americans, sometimes successfully doing so. The countries that he referenced in these examples: Somalia, Morocco, Uzbekistan (he asked the crowd where it was located), Syria, Afghanistan, the Philippines, Iraq, Pakistan and Yemen (which he pronounced "yay-men"). Trump's staff has yet to confirm if there are countries from which the nominee wants to limit immigration. 

"We're letting people come in from terrorist nations that shouldn't be allowed because you can't vet them," Trump said. "There's no way of vetting them. You have no idea who they are. This could be the great Trojan horse of all time."

At another point in the rally, Trump said: "Hillary Clinton wants to have them come in by the hundreds of thousands, just remember. This has nothing to do with politics, folks. This is a whole different level. This has to do with pure, raw stupidity. Okay?"

Republican presidential candidate Trump returned to blasting Democratic rival Hillary Clinton August 4 saying, "If Obama had to do it again, he would have never picked her, never, as Secretary of State." (Reuters)

Trump has long called for a crackdown on illegal immigration, which he has framed as a national security concern. In his announcement speech last year, Trump described illegal Mexican immigrants as rapists and criminals. At numerous rallies, mothers and fathers whose children have been killed by illegal immigrants have shared their heartbreaking stories. Trump has said that building a wall along the border with Mexico will not only keep out illegal immigrants but also criminals, drug traffickers and terrorists. And he has proposed deporting the millions of immigrants illegally living here, starting with those who have committed crimes.

For more than 10 months, Trump has opposed allowing any Syrian refugees into the country because they could be terrorists, and he has promised to kick out all Syrian refugees currently in the country. In December, Trump called for "a total and complete shutdown of Muslims entering the United States until our country's representatives can figure out what is going on." Last month Trump said that his position on banning Muslims has "gotten bigger," as he's now focusing on territories with terrorism problems. Last week Trump told Fox News' Sean Hannity: "People don’t want me to say 'Muslim.' I guess I prefer not saying it, frankly, myself. So we’re talking about territories." But he has yet to say which territories he would target.

About 13 percent of 318.9 million people living in the United States in 2014 were immigrants, according to the Migration Policy Institute, which is a massive increase from 1970, when the rate was less than 5 percent. Mexico is the most common home-nation of these immigrants, followed by India, China and the Philippines.

Within minutes of taking the stage in Maine on Thursday afternoon, Trump warned the crowd of outsiders "pouring into our country," and he promised to build a wall along the border. He was interrupted by protesters who held up pocket-sized copies of the Constitution. The crowd booed and then chanted: "USA! USA! USA!"

A group of protesters held up pocket constitutions at a Trump rally in Portland, Maine, referencing the emotional speech given by the father of Capt. Humayun Khan, a soldier killed in Iraq during the Democratic National Convention. (The Washington Post)

As the protesters were led away, Trump resumed: "A Trump rally is the safest place in our country to be. Believe me. Believe me. Right? It is safe. But if we keep going the way it is, our whole country is becoming different."

Trump warned the crowd that "radical Islamic terrorism" is the "most important issues facing civilization right now" and that the United States has to be more careful in allowing foreigners to visit or move here.

"We've just seen many, many crimes getting worse all the time, and as Maine knows -- a major destination for Somali refugees. Right? Am I right?" Trump said, as the crowd affirmed what he had said. "Well, they're all talking about it: Maine. Somali. Refugees. We admit hundreds of thousands, you admit into Maine, and to other places in the United States. Hundreds of thousands of refugees, and they're coming from among the most dangerous territories and countries anywhere in the world -- right? -- a practice which has to stop. It has to stop... This is a practice that has to stop."

To back up this point, Trump rattled through a list of cautionary examples -- nearly all of which appear on a list of 26 examples released in November by Sen. Jeff Sessions (R-Ala.), a senior member of the Judiciary Committee who chairs an immigration subcommittee. Sessions has closely advised Trump for months and one of his former aides, Stephen Miller, is now a senior policy adviser to Trump and often speaks at Trump's rallies about the dangers of immigration. In nearly each example, Trump noted that the suspect in question came to the United States legally and was granted citizenship.

"They're the ones we know about. There are so many that we don't know about. You're going to have problems like you've never seen," Trump said. "We don't know where these people are. You know when the government puts them around... for the most part, very few people know where they even are. We don't even know where they are located. I'm telling you, I've said it before: This could be the great Trojan horse of all time. They're coming in. They're coming in."

Here are the examples Trump gave:

Somalia: Trump referenced a Washington Times article about thousands of Somali refugees resettling in Minnesota and "creating an enclave of immigrants with high unemployment that is both stressing the state’s safety net and creating a rich pool of potential recruiting targets for Islamist terror groups." The article quotes a FBI official saying Minnesota has seen recruitment videos targeted at Somalis in their state but that authorities have been working closely with the Somali community. "It's happening," Trump said. "It's happening. You see it, you read about it. You can see it." (You can read the full article here: "Feds’ relocation of Somali refugees stresses Minn. welfare, raises terror fears.")

Chechnya: Trump noted that Tamerlan and Dzhokhar Tsarnaev, the so-called Boston bombers, came to the United States " through the political asylum process." Trump did not mention that the brothers were from Chechnya, but he noted that the younger brother became a naturalized U.S. citizen on Sept.11, 2012, while the older brother had an application pending. "Oh that's wonderful, right?" Trump said. "We take them. We take them."

Pakistan: Trump referenced the mass shooting in San Bernardino, although he didn't mention the residency status of the married couple accused of murdering their coworkers. Syed Rizwan Farook was a U.S. citizen, and his wife, Tashfeen Malik, was a permanent resident from Pakistan. At other rallies, Trump has questioned why Malik was allowed to come to the United States on a "fiancee visa."

Morocco: Trump said that a "Moroccan national on a student visa... was arrested for plotting to blow up a university and a federal courthouse." Some background that Trump didn't include: Federal authorities began investigating El Mehdi Semlali Fathi, a native of Morocco who was living in Connecticut on a long-expired student visa. Fathi told a friend he wanted to use "toy planes" to bomb a university and a federal building, but he was never arrested on terrorism-related charges. Instead, Fathi was arrested on immigration-related charges, and in October 2014, he was sentenced to 24 months of imprisonment for fabricating a refugee application. He was set to be deported upon his release.

Uzbekistan: Trump said that a Uzbek refugee living in Idaho -- he paused to ask the audience: "You know where that is? You know where that is, huh?" -- was arrested and charged with "teaching terror recruits how to build bombs." Trump opined: "Oh, wonderful, wonderful. I don't want them in this country." Fazliddin Kurbanov was arrested in 2013 and charged with teaching people to build bombs that would target public transportation. Earlier this year he was sentenced to 25 years in prison.

Syria: Trump said that an immigrant from Syria, who received U.S. citizenship,  planned to kill soldiers on a military base. He was likely referring to Abdirahman Sheik Mohamud, who was born in Somalia and became a naturalized U.S. citizen, settling in Ohio but traveling to Syria to allegedly train with a terrorist organization. Mohamud was indicted on terrorism charges in April 2015, with prosecutors stating that he "wanted to go to a military base in Texas and kill three or four American soldiers execution style.”

Again, Somalia: Trump mentioned the Oregon college student who plotted to blow up a Christmas tree during a lighting ceremony, noting that he was a Somalian refugee who gained citizenship. In October 2014, Mohamed Osman Mohamud was sentenced to 30 years in prison for trying to use a weapon of mass destruction

Afghanistan and the Philippines: Trump said an immigrant from Afghanistan who became a U.S. citizen and a legal permanent resident from the Philippines were convicted of "plotting to join Al-Quada and the Taliban in order to kill as many Americans as possible." In February 2015, Sohiel Omar Kabir, originally of Afghanistan, and Ralph Deleon, a citizen of the Philippines who was a lawful permanent U.S. resident, were sentenced to 300 months in federal prison for participating in plots to provide material support to terrorists and kill American military members.

Iraq: Trump said an Iraqi immigrant who applied for and received U.S. citizenship was arrested for lying to federal authorities about pledging allegiance to ISIS and his travels to Syria and wanting to "kill as many Americans as possible, didn't care how." Bilal Abood, who worked for the U.S. military as a translator during the Iraq War, was sentenced to four years in federal prison in May for lying to the FBI about traveling to Syria and sending a tweet that pledged allegiance to Abu Bakr al-Baghdadi, the leader of Islamic State. Abood testified that he traveled to Syria to fight with the Free Syrian Army, which opposes the Islamic State, according to the Dallas Morning News. During the sentencing, the judge said there no evidence suggesting Abood was planning a terrorist attack.

Again, Pakistan: Trump said two immigrants from Pakistan who became citizens were sentenced to "decades-long prison terms for plotting to detonate a bomb in the middle of New York City." In June 2015, brothers Raees Alam Qazi and Sheheryar Alam Qazi were sentenced to 35 years and 20 years in prison for plotting a terrorist attack in New York City in 2012 and assaulting two deputy U.S. marshals while in custody.

Yemen: Trump said an immigrant from Yemen was arrested for trying to join the Islamic State and illegally buying firearms to "kill as many military personnel as possible." A version of Jeff Sessions' list states that this happened in September 2014 but provided no links to additional information.