Barack Obama is an accommodating and engaging fellow who aims to please. And this was important during the campaign, when likability counted for so much in courting voters. Now, however, it could actually be a problem for him as commander in chief. The question is whether his "politics of nice" is appropriate in a sharply divided capital and a dangerous world.

"There is part of America that wants an assertive president, a president who will be tough on adversaries and who can, at least in theory, be scary in dealing with threats from overseas," says Princeton historian Julian Zelizer. So far, Obama doesn't match up with that tough-guy profile, either at home or abroad.[See photos of the Obamas Abroad]

But Zelizer points out that there is another slice of the country that has an entirely different outlook, more in keeping with Obama's style. "There's part of America that wants a tempered president," someone who will reach out to adversaries, avoid seeing issues and people in absolute terms, and avoid confrontation, Zelizer says. "Both are part of the American psyche."

Some of the rising criticism of Obama as too much of a nice guy is familiar from last year's campaign. His opponents, including Democratic candidate Hillary Clinton (now secretary of state) and Republican nominee John McCain, wondered if candidate Obama was too naive and lacked the grit and passion to fight for what he believed in. Clinton even ran TV ads questioning whether Obama was up to handling a crisis, symbolized by a phone and an emergency call ringing in the White House at 3 a.m. McCain criticized Obama on similar grounds and emphasized the notion that the Democratic nominee wasn't strong or sure-footed enough to handle the challenges he would face in the Oval Office.[Read 10 Power Players and 5 Opponents in Obama's Washington]

Since taking over in January, Obama hasn't changed his tune. He has continued to extend his hand to adversaries at home and abroad, and he has expressed the hope that those adversaries will reward his goodwill with compromise and conciliation. At the same time, on some major decisions, he has shown the kind of backbone that his critics claimed wasn't there. White House aides point out that he sent 30,000 additional troops into Afghanistan to root out terrorists, and he showed no qualms about authorizing Navy sharpshooters to kill Somali pirates who were holding an American captain hostage on the high seas. He also displayed considerable audacity by challenging conservative orthodoxy in undertaking the biggest surge of government activism since the 1960s.[Read Obama's 12 Most Important Decisions]

On domestic issues, Obama has effectively used his philosophy of accommodation to work his will by deferring to Democratic congressional leaders to push his agenda through Congress. It worked for at least a while as he won approval for his $787 billion economic stimulus package and major moves to bail out the financial industry that was approaching meltdown.

But lately, his can't-we-all-just-get-along approach has run into serious trouble. Last Sunday, Sen. Lindsey Graham, a South Carolina Republican, blasted Obama's moderate response to the government crackdown after the disputed presidential election in Iran. "The president of the United States is supposed to lead the free world, not follow it," Graham said on ABC's This Week. "He has been timid and passive more than I would like."

Democrats in Congress would like him to take a stronger stand on his signature initiatives--specifically to clarify which provisions of an emerging health-care overhaul he will insist on and which ones he will refuse to accept. He is similarly faulted for letting fellow Democrats in Congress take the lead in fashioning energy legislation, immigration bills, spending priorities, and other high-priority measures without much clear direction from him, the critics say.

Obama has dealt with the criticism in typically genial fashion. At his White House news conference Tuesday, he denied that his response to the government crackdown in Iran was tepid. He said he has taken a balanced approach--between supporting reformers and, on the other hand, not meddling in Iranian affairs, which he fears could backfire and inflame anti-American sentiment in Iran and throughout the Mideast. But Obama did take a harder line by issuing his harshest criticism of the Tehran regime to date. He said he was "appalled and outraged" at the "threats, beatings, and imprisonments of the last few days," and added: "I strongly condemn these unjust actions."[Read Obama Walks a Fine Line on Iran]

On healthcare, his No. 1 priority, he declined to get specific about his bottom line and defended his approach of letting Congress work out the details. "We have not drawn lines in the sand other than that reform has to control costs and that it has to provide relief to people who don't have health insurance or are underinsured," he said.[Read Tallying the Bill for Healthcare Reform]

Just as important, it's unclear how much pressure Obama and his key aides are exerting on key members of Congress privately, which could make a big difference. Senior strategists of both parties say that even if a president tries to stay above the fray, he can still play hardball and inspire political fear if he authorizes his aides to do it on his behalf. George W. Bush did this through Vice President Dick Cheney and senior adviser Karl Rove. Ronald Reagan did it through White House Chief of Staff Donald Regan and, on personnel matters, via first lady Nancy Reagan.[Read Obama's Congressional Friends (and Foes)]

In Obama's case, much of the head-knocking could be left to key aides such as veteran Washington infighter Rahm Emanuel, a former congressman from Chicago and now White House chief of staff. "If Obama is too nice a guy, Rahm Emanuel certainly isn't," says a former Reagan adviser who has strong ties to the conservative movement. "Obama has some sharp elbows at his disposal if he wants them." They also include Defense Secretary Robert Gates, National Security Adviser James Jones, and counselor David Axelrod.[Learn About the Members of Obama's Inner Circle]

This above-the-battle approach might be a particularly effective gambit for Obama because he faces a split between liberals and centrists in the Democratic Party. "There is this underlying unrest about spending and whether he is spending too much and its effect on the economy," Zelizer says. White House advisers say that, for now, it's best for him to stay in the background rather than alienate either faction.

But they admit that he might have to ruffle some feathers at the end of the legislative process when he will need to make wrenching decisions on the fate of his major priorities. Then the challenge will be for Mr. Nice Guy to show that he can be a tough customer after all.

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