Specifically, will Britain ever again be able to partner with the United States in any future military interventions? Without Britain, the United States will certainly carry on. It has a new best friend in France — french fries top of the menu now! — and maybe Turkey will be willing, too. In the UK, Prime Minister Cameron says Britain will remain committed to mobilising opposition to the Assad regime, delivering humanitarian aid, and deploring the use of chemical weapons.

George Osborne, the chancellor, said that the U.S.-UK relationship was a “very old one, very deep and operates on many layers.” President Obama, in an astonishingly passionate speech he gave to the UK Parliament in May 2011, agreed, calling it “one of the oldest, one of the strongest alliances the world has ever known.”

After the vote, both sides did a bit of squirming, saying that democracies sometimes bite leaders’ bottoms. And, to be sure, the UK and the U.S. have taken quite different views since World War Two — on the Anglo-French-Israeli invasion of Suez, on Vietnam, on the U.S. invasion of Grenada — with “bruises on both sides” (as a U.S. memo on the Grenada row between Margaret Thatcher and Ronald Reagan put it), but no lasting damage. 

Yet a former British ambassador to the U.S. — speaking anonymously — told me he thought that this was a profound moment, rather than just an awkward episode. He is likely to be right: the business end of the special relationship — the willingness of the UK to partner the U.S. in military actions — is likely being held hostage to British public opinion. That public is in no mood to accept warnings of future but unproven risks, judgments based on intelligence and strong leadership into entanglement in foreign wars. Indeed, “intelligence” is now seen, among many, as equal to “stupidity.”

During the Commons debate Jack Straw, Foreign Secretary when the UK was with the U.S. in the invasion of that country in 2003, said  that the shadow of Iraq “has made the public much more questioning.” There is good reason to question. The former U.N. under secretary and advisor to the Foreign Office in the Blair governments, Michael (Lord) Williams, who spent many hard years in the Middle East, told me that he fears that a government that replaced Assad’s would be worse, and that Syria’s many minorities — Christians, Druze, Kurds, Alawites — would be in great danger.

MPs are now much more beholden to their electorates, who, polls show, are hostile to action. The widespread — and erroneous — belief that the Tony Blair government lied to get the UK into the Iraq war lies like a London fog over any debate on new actions. Britain may be out of action for the foreseeable future. The former director of policy planning in the U.S. State Department in the first George W. Bush administration was blunt about it: the UK, he wrote, is now joining the “demilitarization of Europe” and “is in danger of separating itself from both the EU and the U.S.” The former Ambassador to Washington noted that the vote puts Britain in the same position as Germany: firmly in the Western camp, unable to do match words with deeds.

The United States has its guilty reflexes over Iraq, too: and this president, an opponent of the action in 2003 when a senator, has ever been among the most firmly skeptical about foreign wars. David Cameron shared much of his skepticism on this, with both stressing the difficulty and the uncertainty of a strike — though, ironically, Cameron had seemed the more eager for engagement. But unlike the UK, the U.S. must, at certain times, act: it’s still the world’s policeman. Britain has no such compulsion: and now, it has no such ability. 

The U.S. must act, too, because Obama was right about the red line. Though chemical weapons — for all the agonizing death they cause, as we’ve seen in the terrible images from Damascus — are less destructive than biological or nuclear weapons, still they are with them in the WMD basket and have been the subject of treaties banning their use since 1925 Geneva Protocol, strengthened by the Chemical Weapons’ Convention signed in 1993. These treaties have been flouted, but not often — by the Italians in Abyssinia in 1935, the Japanese in China between 1938 and 1941 and by Saddam Hussein’s Iraq against the Iranians in the 1980s and the and Kurds in 1991. If, now, the use of chemical weapons goes unpunished, the conclusion will quickly be drawn that others can use them because the West will huff and puff but blow no houses down. 

There is the possibility of a rethink. Ed Miliband, the Labor leader, probably didn’t mean — when he led his MPs to vote against the government motion asking for assent in principle to intervention, to take any prospect of military action off the table. Many and powerful have been the voices pleading for the vote not to be final. But the risk — stark and shocking in its suddenness — is that Britain has now detached itself from the willing — those willing to fight, at least at times, against tyranny and against indiscriminate slaughter.

The Government has, for the first time in a century, lost a vote on going to war. President Francois Hollande of France now prepares, with President Obama, to shoulder the burden of intervention: the two states whose 18^th century revolutions shattered European autocracy now prepare to shatter the Syrian dictator. Britannia has not ruled for many a decade — now it doesn’t even follow.