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"America's proud to stand shoulder-to-shoulder with these nations on behalf of our common security," he said from the grounds of the White House.
He also touted the bipartisan support he has gathered for the airstrikes from both Republicans and Democrats.
"America is always stronger when we stand united," Obama said.
Obama's statements come the morning after the U.S. launched airstrikes against ISIS targets inside Syria.
The Pentagon justified the strikes, saying that they targeted Khorasan, a part of al Qaeda that US military forces reported were in the process of plotting an attack against Western targets.
"We believe they were nearing the execution phase in either europe or the homeland," Lt. Gen. William Mayville said at a briefing this morning.
He added, "Strikes like this in the future can we expected."
Obama said the U.S. "will do what is necessary to defend our country."
"These terrorists can't find safe haven anywhere," he said.
Up to 20 targets were hit, according to the Pentagon, many of which near the alleged ISIS stronghold of Raqqa.
Obama is headed to New York later today to address the United Nations.
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