LONDON (AP) -- David Cameron seemed the picture of a confident national leader when he cut short his vacation early this week to muster support for a military reprisal against Syria for its purported use of chemical weapons against civilians. He stood with President Barack Obama, facing down a dictator, demanding respect for international law.
By Friday, the prime minister had been laid low by domestic politics, having grievously misread the British appetite for another adventure in the Middle East after the bloody, inconclusive engagements in Afghanistan and, particularly, Iraq, where the British public felt misled and rushed to war by faulty intelligence linking Saddam Hussein to weapons of mass destruction.
A humbled Cameron now finds himself rebuked by Parliament -- a setback so rare that some historians say they have to look back more than two centuries to find a similar defeat over a vital matter of war and peace.
George Jones, professor emeritus of government at the London School of Economics, compares the House of Commons' decision about Syria to its vote in 1782 to have British forces call it quits during the American Revolution.
"The last time the government was knocked off course by Parliament like this was in the 1780s when Parliament accepted that we'd lost the war of American independence and gave up America, so this is a pretty important event," said Jones. "If the government can't get through its policy of war and peace, it's an issue of confidence. Its competence has been shattered."
Jones said the crisis engulfing Cameron is of the prime minister's own making because the Conservative Party leader chose to recall Parliament from its summer recess to seek authorization for a military strike.
Cameron quickly lowered his sights, however, when opposition Labour Party leader Ed Miliband refused to back the measure unless the United Nations Security Council first authorized an attack on Syria. Cameron agreed to ask Parliament only to agree to military strikes in principle and promised to seek a second vote before taking action, but even that watered down version was defeated.
"Cameron has been rowing back frantically as he saw there wasn't support for his position, within his own party, in the opposition, and above all in public opinion," Jones said. "Polls show the British public was not supportive, and the MPs were getting that message from their constituents. The only sure result is that the standing of Miliband rises."
Miliband has not been seen by many as a forceful figure as the leader of the opposition since besting his brother David in a leadership contest in 2010, but he was effective this week in bringing the government's military plans in line with public opinion.
He seemed more attuned than Cameron to acute public doubts about government claims that developed a decade ago when Prime Minister Tony Blair's intelligence-backed assertions that Iraq possessed weapons of mass destruction during the run-up to the Iraq war proved hollow.
When Cameron's government released intelligence reports on Thursday indicating it was "highly likely" that the Syrian regime of President Bashar Assad was responsible for the lethal chemical attack that independent groups believe killed about 355 civilians, the evidence seemed unconvincing to many legislators who said Britain should wait until U.N. inspectors report their findings.
On Friday, Downing Street said Cameron explained to President Barack Obama in a phone call that he wanted to build a "consensual approach in Britain" regarding Syria, and that the government had accepted Parliament's clear rejection of British military action. Obama "fully respected" Cameron's approach, a statement said.
Historian Antony Beevor, author of "The Second World War" and many other books, said misgivings about the way Iraq was handled helped shape the parliamentary debate that damaged Cameron.
"People feel so strongly about the way they were misled over Iraq that they were very skeptical," he said. "The country was even less behind strikes on Syria than Parliament. Polls show maybe about 10 percent backed it. But I think this was a very healthy development. Cameron misjudged the mood of the country, and I think it's absolutely right that he said he'd accept the voice of the House of Commons."
Beevor said it would be foolish to think Cameron has suffered a fatal blow to his hopes for success in the next general election, expected in May 2015.
"He's made several mistakes of judgment recently. This isn't the only one," Beevor said. "But I don't think this is a massive blow. The Labour Party will crow about it, but I think the real reaction across the country will be one of relief."
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