Barack Obama says: "John McCain is determined to carry out four more years of George Bush's failed policies." Obama is a politician, so it's normal that he'd choose to repeat the lines that some of his followers want to hear. But before people buy that argument, I'd ask them to read three speeches.

The first was delivered by McCain on Sept. 28, 1983. The Reagan administration was seeking Congressional authorization to support the deployment of U.S. Marines in Lebanon. McCain, a freshman legislator, decided to oppose his president and party.

McCain argued that Lebanese society, as it existed then, could not be stabilized and unified by American troops. He made a series of concrete observations about the facts on the ground. Lebanon was in a state of de facto partition. The Lebanese Army would not soon be strong enough to drive out the Syrians. The American presence would not intimidate the Syrians into negotiating.

"I do not foresee obtainable objectives in Lebanon." He concluded. "I believe the longer we stay, the more difficult it will be to leave, and I am prepared to accept the consequences of our withdrawal."

This was not the speech of a man who thinks military force is the answer to every problem. It was the speech of one who conforms policies to facts. And it came a month before a terrorist attack that killed 241 Americans.

The second speech was delivered on Nov. 5, 2003. This was not a grand strategy speech. It was a critique of the execution of existing U.S. policy.

First, McCain wondered about the Pentagon's publicity campaign in Iraq: "When, in the course of days, we increase by thousands our estimate of the numbers of Iraqis trained, it sounds like somebody is cooking the books."

He then pointed out that the U.S. had not committed sufficient troops. He called for a counterinsurgency strategy in which U.S. forces would actually hold secure territory. "Simply put," he said, "there does not appear to be a strategy behind our current force levels in Iraq, other than to preserve the illusion that we have sufficient forces in place to meet our objectives."

He excoriated the arrogance of Paul Bremer and the Coalition Provisional Authority: "The C.P.A. seems to think that all wisdom is made in America, and that the Iraqi people were defeated, not liberated."

This was the speech of a man, adjusting to changing circumstances, who was calling on the administration to adjust quickly as well.

The third McCain speech was delivered on Wednesday. It is as personal, nuanced and ambitious a speech as any made by a presidential candidate this year.

McCain noted that we are not only fighting a war on terror. The world is seeing a growing split between liberal democracies and growing autocracies. We are seeing a world in which great power rivalries - with China, Russia and Iran - have to be managed and soothed.

Moreover, the U.S. is not the sole hegemon. Power is widely distributed among many rising nations. McCain's core purpose in the speech was to revive the foreign policy tradition that has jumped parties but that has been associated with people like Theodore Roosevelt, Henry Stimson, Dean Acheson, John Kennedy and Ronald Reagan.

In this tradition, a strong America is the key to world peace, but America's role is as a leading player in an international system. America didn't defeat communism, McCain said Wednesday, the American-led global community did. This is the tradition that Robert Kagan of the Carnegie Endowment has been describing for a decade.

McCain offered to build new pillars for that system - a League of Democracies, a new nuclear nonproliferation regime and a successor to the Kyoto treaty. In stabilizing Asia and the Middle East, he would rely more on democracies like Turkey, India, Israel and Iraq, and less on Mubarak and Musharraf.

Unlike the realists, McCain believes other nations have to be judged according to how they treat their own citizens. Unlike the Bush administration in its first few years, he believes global treaties cannot solely be evaluated according to a narrow definition of the American interest. The U.S. also has to protect the fabric of the international system.

McCain opened his speech with a description of his father leaving home on the day of Pearl Harbor, and then being gone for much of the next four years. He harkened back repeatedly to the accomplishments of the Truman administration.

In so doing, he signaled that the foreign policy debate of the coming months will be very different from the one of the past six years. Anybody who thinks McCain is merely continuing the Bush agenda is not paying attention.