WASHINGTON - President Barack Obama is poised to become the first U.S. leader in three decades to attack a foreign nation without mustering broad international support or acting in direct defense of Americans.
Not since 1983, when President Ronald Reagan ordered an invasion of the Caribbean island of Grenada, has the U.S. been so alone in pursing major lethal military action beyond a few attacks responding to strikes or threats against its citizens.
It's a policy turnabout for Obama, a Democrat who took office promising to limit U.S. military intervention and, as a candidate, said the president "does not have power under the Constitution to unilaterally authorize a military attack in a situation that does not involve stopping an actual or imminent threat to the nation."
But over the last year Obama has warned Syrian President Bashar Assad that his government's use of chemical weapons in its two-year civil war would be a "red line" that would provoke a strong U.S. response.
So far, only France has indicated it would join a U.S. strike on Syria.
Some lawmakers in Obama's party hedged in supporting an attack with little foreign backup.
"The impact of such a strike would be weakened if it does not have the participation and support of a large number of nations, including Arab nations," Senate Armed Services chairman Carl Levin, a Democrat, said Friday.
Without widespread backing from allies, "the nature of the threat to the American national security has to be very, very clear," said retired Army Brig. Gen. Charles Brower, an international studies professor at Virginia Military Institute in Lexington, Va.