By Paul Reynolds
World affairs correspondent BBC News website
In his first 100 days, President Barack Obama has shown an ability to soothe ruffled feelings about the United States left by George W Bush.
There is no good reason why the US and Russia should not get on well
His approach has been to calm global nerves, including economic ones, drop the neo-conservative rhetoric and some of the practices of the Bush years, reach out to many (but not all) adversaries and to signal that the United States is again interested in multilateralism as a diplomatic tool.
He is not in the business of changing the world as George Bush was.
However, applying a balm does not by itself solve the underlying problems.
Goodwill will not be enough.
Take the two major items on the international nuclear agenda, North Korea and Iran, as examples. Within this 100 days, North Korea has abandoned its commitment to stopping its nuclear work and has broken off the talks that were the vehicle for constraining it. On this front, the old rules still apply. North Korea blows hot and cold.
On the other front, Iran has shown no interest in stopping the enrichment of uranium - the major demand of the Security Council. Iran is considering its position after an offer of talks by the new administration but will not be an easy fish to hook.
An earlier US president, Jimmy Carter, who also tried to formulate a new American foreign policy after a period of turbulence, himself ran into the revolutionaries in Tehran. It is not a good omen.
Then there is the war in Afghanistan. For all the talk about a new policy there, with an emphasis on politics and greater efforts to pacify the border regions of Pakistan, the major element of the Obama policy is a significant increase in the number of US troops.
Many American presidents fight wars they would rather have avoided. Harry Truman found himself up to the hilt in Korea. John Kennedy was drawn into Vietnam. Lyndon Johnson was destroyed by Vietnam. Even Bill Clinton, reluctant to deploy US troops, launched war (though from the air) against Serbia.
Being reluctant to fight does not mean being unwilling to fight, as Barack Obama has already shown in Afghanistan.
Of course, diplomacy is not all about solving problems. It is often more about managing them.
Here the early results seems to be promising. The US relationship with Russia is an example. There is no good reason these days why the US and Russia should not get along well enough and even reach agreements. One such agreement, to reduce nuclear weapons, is likely by the end of the year. Problems between them (the missile defence system being a main one) could be managed, if not resolved.
The reaching-out formula might bring dividends in the Islamic world. Support for al-Qaeda might be undermined. But leaving Iraq will probably have more effect. Which what he intends to do. His supporters define that as smart diplomacy - get the atmospherics right but get the actions even more right.
And talking of atmospherics, President Obama has offered more goodwill on global warming (for some the defining issue of the age) but here again, the real policies have yet to come.
And the Middle East? No president has resolved this, though a few solved bits of it. President Obama will not be in office for the 100th anniversary of the 1917 Balfour Declaration, which allowed a "national home" for the Jewish people in Palestine. But come November 2017, another president may well still be grappling with the problem.