It was the kind of occasion that reminds senior White House officials that access to the president is not always such a wonderful thing.

On the night of May 7, it fell to national security adviser Samuel R. "Sandy" Berger to track down President Clinton on a political trip in Texas to share the latest bad news from the air war: NATO bombs had mistakenly destroyed the Chinese Embassy in Belgrade.

The anger at the other end of the line was swift and unmistakable. "He was upset that it happened, baffled by how could it happen, insistent on getting an explanation of what went wrong," Berger recalled recently.

But Clinton's storm may have been as noteworthy for what it was not.

The errant bombing was the kind of event that in an earlier time might have triggered profanity and blame-casting, followed by self-pity and self-doubt, say many past and current Clinton advisers and friends. But Berger heard none of this: "He wanted people focused on how to fix the problem rather than going on a witch hunt. . . . He focused on how we deal with this and keep moving forward."

There has been a different Clinton on display during this spring's Kosovo crisis. In the past, Clinton has been a president given to seeing merit on all sides of an argument and who sometimes has swerved between policies in the face of criticism. Yet, in the past two months, despite suffering through waves of bad news, second-guessing by experts and declining approval ratings, Clinton has held steadfastly to his underlying goal of ending repression in Kosovo on NATO's terms.

Is Clinton, after more than six years in office and countless personal and political crises, a changed man?

"He whines less and fights more," longtime friend and political strategist James Carville said. "He understands he's going to get bad news and accepts it."

To be sure, some of Clinton's familiar traits -- a tendency to lurch into crises and to improvise his way out of them -- also were on display in these recent months. Critics say the Kosovo war could have been avoided in the first place through more farsighted diplomacy. Once the war began, many military experts said Clinton failed to see that the air campaign would not work in a short period of time.

But such complaints will look like quibbles if Yugoslavia follows through on its stated acceptence of NATO demands, say Clinton aides. Still uncertain, various Clinton advisers said, is what effect NATO's apparent victory will have on the 19-month balance of his presidency. Some presidential aides and friends are describing Kosovo in Churchillian tones, as Clinton's "finest hour." Yet by all indications he is eager for the hour to pass rapidly.

On Thursday, the day Yugoslav President Slobodan Milosevic said he accepted NATO's demands, Clinton welcomed that announcement in the Rose Garden, then pivoted to remarks on Medicare and environmental protection. His radio address Saturday was not a reflection on the NATO alliance's first war, but a pledge to devote more federal attention to mental health issues.

The abrupt change of focus was no accident. Public unease over the Kosovo conflict, several Clinton advisers said, contributed to what various polls have shown is a steady drop in Clinton's public approval rating.

Most Clinton aides expect no dramatic spike in the wake of a successful Kosovo exit. One Democratic strategist who is influential at the White House said foreign policy for the American president is like snow removal for a big-city mayor: You get little credit when things work well, but punishment when they don't.

Yet several current and former close advisers were struck by the relative detachment with which Clinton watched his approval ratings fade in recent weeks. For nearly four years, after Clinton's humiliation in the 1994 midterm elections, keeping approval ratings high was a preeminent project of his presidency. Clinton, friends said, expressed alarm when the numbers dropped even a point or two; during the impeachment battle, one aide said, he "was forever spouting poll numbers."

From the White House vantage, Clinton's survival -- whether fighting for reelection or trying to avoid removal from office in the Lewinsky scandal -- depended on keeping those numbers high. They were also key to doing anything more ambitious, providing the stick with which he could prod congressional Republicans and Democrats to join him in fashioning a centrist agenda.

But a friend who was with Clinton when a new batch of anemic ratings arrived on his desk reported with surprise: "He did not flinch. He was calm about it."

This is not to suggest, aides said, that Clinton was oblivious to public perceptions. The day after the Chinese Embassy bombing, Clinton complained to British Prime Minister Tony Blair that news coverage was not fully presenting the moral dimensions of the war, according to notes of the phone call shared by a White House official. Referring to reports of a ghoulish Serbian atrocity, Clinton told Blair: "If we had one TV picture of the 15 men being roped together and burned alive, people would be wondering why we haven't leveled the place."

For all the belligerence of that remark, Clinton's handling of the Kosovo crisis hardly suggests a battle-hungry president, ready to let the consequences be damned. Instead, what Kosovo represents is Clinton's growing ability to integrate the uneasy mix of moralistic and pragmatic impulses that guide his foreign policy.

Once, these two sides seemed in constant battle for control. Clinton the moralist expanded the 1993 U.S. peacekeeping mission in Somalia; Clinton the pragmatist pulled troops home once there were U.S. fatalities. In the 1992 campaign, the moralist accused President George Bush of "coddling dictators" with his China policy; in office, the pragmatist concluded that there was little alternative to continuing Bush's policy.

In Kosovo, Clinton decided that the moral and political implications of letting Serb-led Yugoslav forces overrun and ethnically cleanse Kosovo were unacceptable. But he also decided that only airstrikes, rather than the ground troops that many military experts said were necessary, represented an acceptable cost.

In recent weeks, one foreign policy adviser said, Clinton began reluctantly to reassess that judgment, confronting the possibility that even ground troops might be preferable to defeat. This official said Clinton began casting the issue in historical terms, saying, "This is not Vietnam. But it's also not the Persian Gulf War."

In other words, a Kosovo ground war would not be an unwinnable quagmire like Vietnam. But, the official said, "He also did not accept that after we bombed them for 80 or 90 days, a ground victory would be a piece of cake. He thought it was a very expensive option in lives and dollars."

The lessons of the past also echoed in personal ways. One friend who has spoken to Clinton several times in recent months believes Kosovo -- and what Clinton believes were the unambiguously moral motives for NATO's intervention -- represented a chance to soothe regrets harbored in Clinton's own conscience.

One of those regrets concerned Vietnam, a war Clinton believes was a mistake and took steps to avoid serving in. The friend said Clinton has at times lamented that the generation before him was able to serve in a war with a plainly noble purpose, and he feels "almost cheated" that "when it was his turn he didn't have the chance to be part of a moral cause."

A more recent regret concerned the year of sexual scandal that ended the month before the Kosovo air war began. Once, after the Middle East peace accord at Wye River last fall, Clinton publicly said he was rededicating himself to doing good things as president. Friends say he has expressed the same sentiment more frequently in private.

Compared with what Clinton viewed as the low-minded nature of the Lewinsky scandal, this confidant said, in Kosovo the president believed, "This is something big; this is something important. . . . There was a sense that if this costs him points, at least it was in the service of something moral."

Another friend said the regular "spiritual counseling" that Clinton is receiving in the wake of the Lewinsky scandal has helped him curb a tendency to vent anger and lose focus on the larger picture when things aren't going well.

Whatever the reasons, Kosovo suggests a changed relationship between Clinton and those around him. Often it fell to people prone to certitude -- such as Hillary Rodham Clinton or consultant Dick Morris -- to help Clinton quell his doubts and steel his confidence.

In Kosovo, it was Clinton himself who played this role. After the opening days of the air war, when NATO's attacks were accelerating rather than deterring Milosevic's ethnic cleansing in Kosovo, one administration official said the mood on Clinton's foreign team was like that among people who jumped off a plane and only afterward asked themselves, "I wonder if this parachuting thing is a good idea."

But Clinton gave several pep talks to his team, encouraging Secretary of State Madeleine K. Albright not to despair over unflattering publicity, assuring the group that if things did not work, it would be his fault and not theirs.

Yet Jesse L. Jackson, who provided critical support to Clinton during the impeachment battle, said that Clinton was ill-served by his advisers and that he believed the president appeared to wander into war by accident. It was during impeachment, Jackson said, when Clinton's attention was diverted, that Albright and others tried to force an unworkable peace plan at the Rambouillet negotiations, presenting Milosevic the choice of war or capitulation. "If he had been more focused, the Rambouillet conference would have turned out better," Jackson said.

Jackson recalled a meeting with the president and his team after he returned from Belgrade, where he persuaded Milosevic to release three captured U.S. soldiers. Clinton responded enthusiastically when Jackson said Milosevic needed to be shown how a negotiated settlement was in his interest, but Albright condemned the idea of a bombing pause. "Others were in the demonization business," Jackson said, adding that Clinton "tends to do better following his own instincts and insights rather than those of his advisers."

Rather than a victory, what Clinton has achieved in Kosovo, critics say, is long-term U.S. ownership of an unstable part of the Balkans that remains essentially in civil war. However much this criticism may sting, it is a fraction of what would have come had Milosevic not yielded last week. Clinton's team members plainly feel that events in Kosovo have given them the right to boast.

"This has brought together everything Clinton has, and everything he has learned, about leadership," Berger said. "He's conveyed a sense of steadiness that's been extremely important in an enterprise that many people outside the government believed could not possibly work."