Washington ? Tony Blair and Jacques Chirac could have changed Europe – and perhaps the world – if they had been able to work together. Instead they became bitter rivals who are surrendering power at the same time and in the same condition. Both are leaving office deeply unpopular at home and far short of their ambitious foreign policy goals.

The British prime minister will enter history as a leader with great romantic ideas who tried to do too much and failed. The French president’s final legacy is that of a political cynic who tried to do too little and also failed.

In 1998, a promising French-British attempt at cooperation on European defense made the two leaders appear to have a joint vision for Europe and global affairs. But the effort faltered and an enduring hostility arose to block the greater European unity both professed to want. Blair would become President Bush’s closest ally abroad while Chirac became the American president’s sharpest critic on the Iraq war.

Temperament as much as national interests doomed the two to take conflicting paths.

While Blair earnestly wears his romanticism on his sleeve, Chirac hides a deep core of cynicism under a genial, gallant and gregarious exterior. More than a dozen conversations with him over the years in the presidential Elysee Palace, the prime minister’s office or when he was mayor of Paris were unfailingly friendly, funny and all about Jacques Chirac.

Conversations with Blair at 10 Downing Street were all about work. They centered on his determination to change Britain and the world through the force of ideas and, where necessary abroad, the use of force. The political right should have no monopoly on power projection in the world, he once told me.

Blair, elected from the left in 1997, has governed for a decade from the center right. Chirac, who won the presidency on his third try in 1995 as a conservative, quickly retreated into defending leftist welfare programs to keep social peace after reform programs triggered unrest in the streets. In the end, neither leader was able to keep control over his party’s professionals and militants, who felt they had been abandoned. In the end, both paid a high price for that.

Blair’s support of successful “humanitarian intervention” in Bosnia, Kosovo, Sierra Leone and elsewhere pushed him toward regime change in Iraq in 2003. Like many of us, Blair had an overly romantic idea of how Iraq would function under what became a misconceived and mismanaged occupation. But his mistake was his own, not something dictated to him by the Bush administration.

Moreover, his strong sense of historical optimism would have been reinforced by his considerable domestic successes. Blair transformed the Labor Party into a modern, centrist political organization capable of managing a vibrant economy.

But the divisions the Iraq war created at home forced Blair to step down. This week he endorsed Gordon Brown, his chancellor of the exchequer, to succeed him this summer on a date to be announced next week. To all intents and purposes, Blair has already lost power.

So has Chirac. His successor will be chosen in elections Sunday and Chirac will leave office by May 17. He has nominally endorsed Nicolas Sarkozy, who has embarrassed the incumbent by calling for sweeping changes that Chirac refused to support and by determinedly taking over control of the right-wing party that Chirac created.

The French praise Chirac for having guessed right about Iraq and for standing up to the intensely unpopular Bush. He will also be remembered for helping bring an end to the bloodletting in Bosnia shortly after coming to office and for showing a fairly flexible attitude on France’s role in NATO.

But Chirac has been unable to give content or direction to a French role in the “multipolar world” he has often described but not successfully defined. The angry rejection by the French electorate in 2005 of a proposed European constitution – a rejection that expressed in part dissatisfaction with Chirac’s rule – has left the European Union confused and adrift. Chirac’s championing of EU membership for Turkey has been repudiated by Sarkozy and by the nation.

Chirac pursued and used power for what it would bring to him and to France. It was the goal in itself. Blair saw power as a tool for changing Britain and the world. By different routes the two leaders arrive at the same destination, looking back on what might have been.