President Barack Obama said Monday that sending troops into Syria to fight ISIS would be a "mistake," but not allowing Syrian refugees into the United States would betray American values.
"Not because our military could not march into ... Raqqa and temporarily clear out ISIL, but because we would see a repetition of what we've seen before," he said in a speech at the G-20 meeting in Turkey. "If you do not have local populations that are committed to inclusive governance and who are pushing back against ideological extremes, then they resurface."
"Let's assume we send 50,000 troops into Syria. What happens when there is a terrorist attack generated from Yemen? Do we then send more troops into there?"
Obama made his remarks after the the deadly attacks in Paris carried out on Friday by the so-called Islamic State left at least 129 dead and hundreds more injured.
Obama reaffirmed the need to accept refugees from Middle East war zones who are flooding into Europe.
"At the same time, all of our countries have to ensure our security, and as president, my first priority is the safety of the American people," he said. "Even as we accept more refugees — including Syrians — we do so only after subjecting them to rigorous screenings and security checks. We also have to remember that many of these refugees are the victims of terrorism; that's why they're fleeing."
Obama has come under sharp criticism by Republicans. The Republican governors of three states, Texas, Alabama and Michigan, said they would not allow Syrian refugees in their states. GOP presidential candidate Donald Trump told CNBC on Monday "You can't let them in" because "it would be one of the great Trojan horses."
At the G-20 meeting, Obama met on the sidelines with Russian President Vladimir Putin on Sunday.
"President Obama and President Putin agreed on the need for a Syrian-led and Syrian-owned political transition, which would be proceeded by U.N.-mediated negotiations between the Syrian opposition and regime as well a ceasefire," a White House official said, according to NBC News.
The French government reacted to the attacks by declaring a state of emergency and by closing down the country's borders on Friday. France also launched a series of air strikes against ISIS on Sunday.
France has also conducted 168 anti-terror raids, which have led to 23 arrests.
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