President Donald Trump signed two executive orders on Friday that dramatically expand the nation's military and call for so-called "extreme vetting" of visa seekers from terror-plagued countries — moves aimed at strengthening the U.S. response to terrorism both home and abroad.

In signing the order, Trump pledged to "keep radical Islamic terrorists out of the United States of America."

"We are not admitting into the country the very threats our soldiers are fighting overseas," Trump said during the swearing in ceremony for Defense Secretary James Mattis at the Pentagon. "We only want to admit those into our country who will support our country and love deeply our people."



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The order specifically singles out the arrival of Syrian refugees as "detrimental to the interests of the United States" and President Trump has suspended their entry until he feels the vetting process has been strengthened.

This is a complete reversal of a hotly-debated policy set forth by the Obama administration which made a goal last year of admitting 10,000 Syrian refugees driven by the violence that occurred during their nations protracted civil war.

It reached that goal in August.

"The United States feels it is important for us to take our share of Syrian refugees as part of this overall humanitarian effort," Obama said in September.

The State Department in a statement on Friday said it is working with the Departments of Homeland Security and Health and Human Services to put Trump's executive order into effect.

Extreme vetting is an idea that evolved from Trump's controversial Muslim ban that he called for in Dec. 2015, which would address concerns from some over refugees entering the country from terror-stricken nations.

"We've taken in tens of thousands of people. We know nothing about them," Trump said in an interview with Fox News' Sean Hannity on Thursday. "They can say they vet them. They didn't vet them. They have no papers. How can you vet somebody when you don't know anything about them and you have no papers?"

Though the United States government already utilizes a thorough nine-step vetting system for refugees, the president's executive order is said to go further. It is still unclear what these steps would mean and if it would target any particular religious group as the president stated on the campaign trail.

According to the Pew Research Center, the United States welcomed almost 85,000 refugees in 2016. Forty-six percent of them were Muslim.

The president sets the number of refugees accepted annually into the U.S. and from that authority can suspend the program at any time. President George W. Bush took similar actions following the 9/11 attacks when the program was suspended for several months.

Rep. Mike McCaul, R-Texas, chairman of the Homeland Security committee, said on Friday that he applauds the president's move.

"We are a compassionate nation and a country of immigrants. But as we know, terrorists are dead set on using our immigration and refugee programs as a Trojan Horse to attack us," McCaul said in a statement. "Today, President Trump signed an order to help prevent jihadists from infiltrating the United States."

The response from advocates for refugee rights was swift.

"I am heartbroken that today President Trump is closing the door on children, mothers and fathers fleeing violence and war," Malala Yousafzai, a student activist and the youngest-ever Nobel Prize laureate said in a statement through a press office. "I am heartbroken that America is turning its back on a proud history of welcoming refugees and immigrants — the people who helped build your country, ready to work hard in exchange for a fair chance at a new life."

Facebook CEO Mark Zuckerberg took to Facebook to express his concern about the executive order's impact on those fleeing violence and oppression in their homelands. His great grandparents came from Germany, Austria and Poland. His wife, Priscilla's, parents were refugees from China and Vietnam.

"We need to keep this country safe, but we should do that by focusing on people who actually pose a threat. Expanding the focus of law enforcement beyond people who are real threats would make all Americans less safe by diverting resources, while millions of undocumented folks who don't pose a threat will live in fear of deportation," he wrote. "We should also keep our doors open to refugees and those who need help. That's who we are. Had we turned away refugees a few decades ago, Priscilla's family wouldn't be here today."

Trump also called for a "great rebuilding" of the nation's military. "New planes, new ships, new resources, new tools for our men and women in uniform."

"The military defends society, it doesn't define it," Dr. Richard Kohn, a military historian and expert on civil-military relations who teaches at the University of North Carolina, told NBC News. "It doesn't decide when it should be used, it doesn't decide how large it should be or what resources it should have or who should serve and under what circumstances. It's a neutral servant of the state."