Richard Perle, a member of the influential Defense Policy Board, told the International Herald Tribune that if Syria were found to be hiding Iraqi weapons, "I'm quite sure that we would have to respond to that."
"But I suppose our first approach would be to demand that the Syrians terminate that threat by turning over anything they have come to possess, and failing that I don't think anyone would rule out the use of any of our full range of capabilities," Perle said.
The remark is one of several by top U.S. officials and advisers in recent weeks that suggest the U.S. might turn the heat up on Damascus now that Baghdad has fallen.
Along with Libya, Iran and North Korea, Syria is one of the countries the Bush administration has put on notice for its alleged support of terrorism.
Syria's backing of Hezbollah, a group active along the Israel-Lebanon border, is what puts it on this list. Some in Congress feel Hezbollah is a graver threat than al Qaeda and want the U.S. to concentrate on wiping it out.
Only moments after hailing the apparent U.S. victory in Baghdad on Wednesday, Secretary of State Defense Donald H. Rumsfeld turned the heat up on Syria.
He accused Damascus of giving haven to some members of Saddam Hussein's regime and assisting others to additional safe locations. Citing "scraps of intelligence" at a Pentagon news conference, Rumsfeld also renewed his accusation that Syria provided Iraq with night-vision goggles and other military technology.
"They would be well advised not to provide military equipment to Iraq," he said. "I find it notably unhelpful."
Secretary of State Colin Powell, in comments to a pro-Israel group in late March, issued tough challenges to both Syria and Iran.
"Tehran must stop pursuing weapons of mass destruction and the means to deliver them," he said.
"Syria also now faces a critical choice," Powell continued. "Syria can continue direct support for terrorist groups and the dying regime of Saddam Hussein, or it can embark on a different and more hopeful course. Either way, Syria bears the responsibility for its choices, and for the consequences."
Asked days later about what "consequences" meant, Powell told European reporters that President Bush thinks there is a range of methods for dealing with terrorism.
"Sometimes political actions are appropriate, economic actions, use of our intelligence assets. Sometimes military force is appropriate. But we are not looking for wars to get into," he said.
Asked Wednesday if any other countries beyond Iraq were potential targets for use of U.S. military force, Rumsfeld said: "No one is throwing down the gauntlet…I have nothing to announce. We're still dealing with Iraq."
Perle — who in January, 2002, penned an editorial called "The U.S. Must Strike At Saddam Hussein" — also said Syria was not necessarily slated for military attack.
"If next means who will next experience the 3d Army Division or the 82d Airborne, that's the wrong question," he told the Tribune. "If the question is who poses a threat that the United States deal with, then that list is well known. It's Iran. It's North Korea. It's Syria. It's Libya, and I could go on."
"So the message to Syria, to Iran, to North Korea, to Libya should be clear. if we have no alternative, we are prepared to do what is necessary to defend Americans and others. But that doesn't mean that we are readying the troops for a next military engagement. We are not," he said.