An architect of the U.S. war in Vietnam more than 30 years ago said Sunday that he has "a very uneasy feeling" that some of the same factors that damaged support for the conflict there are re-emerging in the 2-year-old war in Iraq.

"For me, the tragedy of Vietnam was the divisions that occurred in the United States that made it, in the end, impossible to achieve an outcome that was compatible with the sacrifices that had been made," former Secretary of State Henry Kissinger told CNN's "Late Edition with Wolf Blitzer."

Support for the war has dropped in recent polls, and criticism of President Bush's handling of the conflict has grown. The latest CNN/USA Today/Gallup poll, taken Aug. 5-7, found that 54 percent of those surveyed thought the 2003 invasion of Iraq was a mistake.

Kissinger said the United States faces a battle to halt the spread of radical Islam in Iraq, and it would be "a catastrophe for the whole world" if it fails.