Talking to adversaries

But critics of the administration's approach say the administration has simply lectured countries such as Syria, refusing to detail concrete benefits that might flow from closer cooperation. Leverett, now at the New America Foundation, interviewed Syria's president, Bashar al-Assad, for a book after he left the White House and said Assad complained that all he heard from U.S. officials was a long list of demands.

Syria is "a state, not a charity," Assad told Leverett. "If it is going to give something up, it must know what it will get in return."

For instance, administration officials have always demanded that Syria prevent militant groups from operating on its territory but have never explained what Syria would get in return. Leverett said the administration should have explicitly linked Syria's removal from the list of state sponsors of terrorism to its expelling groups such as Hamas and severing the links that allow arms to flow to Hezbollah.

Syria also could be induced to cooperate if it receives some acknowledgment that it has a role in an Arab-Israeli peace deal, experts said. Syria nearly reached a peace agreement with Israel during the Clinton administration, but the Bush administration has been reluctant to involve Syria in its peace efforts.