WASHINGTON — For the last 150 years, most American war presidents — most notably Lincoln, Wilson and Roosevelt — have entered (or re-entered) office knowing war was looming. Not so George Bush. Not so the war on terror. The 9/11 attacks literally came out of the blue.

Indeed, the three presidential campaigns between the fall of the Berlin Wall and 9/11 were the most devoid of foreign policy debate of any in the 20th century. The commander-in-chief question that dominates our campaigns today was almost nowhere in evidence during our '90s holiday from history.

When I asked President Bush during an interview Monday to reflect on this oddity, he cast himself back to early 2001, recalling what he expected his presidency would be about: education reform, tax cuts and military transformation from a Cold War structure to a more mobile force adapted to smaller-scale 21st-century conflict.

But a wartime president he became. And that is how history will both remember and judge him.

Getting a jump on history, many books have already judged him. The latest by Bob Woodward describes the commander in chief as unusually aloof and detached. A more favorably inclined biographer might have called it equanimity.

In the hour I spent with the president (devoted mostly to foreign policy), that equanimity was everywhere in evidence — not the resignation of a man in the twilight of his presidency but a sense of calm and confidence in eventual historical vindication.

It is precisely that quality that allowed him to order the surge in Iraq in the face of intense opposition from the political establishment (of both parties), the foreign policy establishment (led by the feckless Iraq Study Group), the military establishment (as chronicled by Woodward) and public opinion itself. The surge then effected the most dramatic change in the fortunes of an American war since the summer of 1864.

That kind of resolve requires internal fortitude. Some have argued that too much reliance on this internal compass is what got us into Iraq in the first place. But Bush was hardly alone in that decision. He had a majority of public opinion, the commentariat and Congress with him. In addition, history has not yet rendered its verdict on the Iraq War. We can say that it turned out to be longer and more costly than expected, surely. But the question remains as to whether the now-likely outcome — transforming a virulently aggressive enemy state in the heart of the Middle East into a strategic ally in the war on terror — was worth it. I suspect the ultimate answer will be far more favorable than it is today.

When I asked the president about his one unambiguous achievement, keeping us safe for seven years — about 6 1/2 years longer than anybody thought possible at the time of 9/11 — he was quick to credit both the soldiers keeping the enemy at bay abroad and the posse of law enforcement and intelligence officials hardening our defenses at home.

But he alluded also to some of the measures he had undertaken, including "listening in on the enemy" and "asking hardened killers about their plans." The CIA has already told us that interrogation of high-value terrorists like Khalid Sheik Mohammed yielded more valuable intelligence than any other source. In talking about these measures, the president mentioned neither this testimony as to their efficacy nor the campaign of vilification against him that these measures occasioned. More equanimity still.

What the president did note with some pride, however, is that beyond preventing a second attack, he is bequeathing to his successor the kinds of powers and institutions the next president will need to prevent further attack and successfully prosecute the long war. And indeed, he does leave behind a Department of Homeland Security, reorganized intelligence services with newly developed capacities to share information, and a revised FISA regime that grants broader and modernized wiretapping authority.

In this respect, Bush is much like Truman, who developed the sinews of war for a new era (the Department of Defense, the CIA, the NSA), expanded the powers of the presidency, established a new doctrine for active intervention abroad, and ultimately engaged in a war (Korea) — also absent an attack on the U.S. — that proved highly unpopular.

So unpopular that Truman left office disparaged and highly out of favor. History has revised that verdict. I have little doubt that Bush will be the subject of a similar reconsideration.

Charles Krauthammer's column is distributed by the Washington Post Writers Group.