WASHINGTON – President Bush yesterday condemned Syria and Iran for collaborating with terrorists, warning that the regimes “deserve no patience from the victims of terror.”

Mr. Bush delivered his comments as part of a broad address that made the case for remaining firm in the war on terror, particularly in Iraq. He also defined the nature of the enemy America faces and outlined his strategy for defeating it.

The president disclosed that America and its allies have disrupted at least 10 Al Qaeda terrorist plots since September 11, 2001, including three attacks planned for inside America. “We’ve stopped at least five more Al Qaeda efforts to case targets in the United States, or infiltrate operatives into our country,” he said.

And Mr. Bush lashed out at “elements of the Arab news media that incite hatred and anti-Semitism, that feed conspiracy theories and speak of a so-called American ‘war on Islam’ – with seldom a word about American action to protect Muslims in Afghanistan, and Bosnia, Somalia, Kosovo, Kuwait, and Iraq.”

Speaking at the Ronald Reagan Building and addressing the National Endowment for Democracy – an institution established under President Reagan, and instrumental in supporting dissident movements that helped bring an end to the Soviet empire – Mr. Bush also framed the battle against radical Islam as heir to America’s historic struggles against other murderous ideologies, particularly communism. He compared terrorists like Osama bin Laden and Abu Musab al-Zarqawi to their dictatorial predecessors, citing Hitler, Stalin, and Pol Pot.

Mr. Bush expressed confidence, however, that Marxism’s fate would also be the terrorists’. “Islamic radicalism, like the ideology of communism, contains inherent contradictions that doom it to failure,” he said in his remarks, attended by Secretaries Rice and Rumsfeld and the new chairman of the Joint Chiefs of Staff, General Peter Pace.

Less than two weeks before liberated Iraqis vote on a new constitution, Mr. Bush also reminded Americans that “the terrorists regard Iraq as the central front in their war against humanity.”

Public-opinion polls have indicated flagging support for the war effort, and recent months have brought increased protests, including a large anti-war demonstration here late last month.

Mr. Bush, however, appeared unfazed yesterday, saying those who believe America would be made safer by “cutting our losses and leaving Iraq now” cling to “a dangerous illusion” and suffer from a “self-defeating pessimism.”

Looking ahead, President Bush singled out Syria and Iran, labeling them “allies of convenience” with radical Islam, and calling them “enemies of civilization” that “use terrorist propaganda to blame their own failures on the West and America, and on the Jews.”

President Bush also stressed how much the ultimate victory over radical Islam would depend on the popular thirst for freedom in the Middle East, praising the work of Afghans and Iraqis in providing military security for their countries alongside American troops, and encouraging democratic reform in Saudi Arabia and Egypt.

“We’re standing with dissidents and exiles against oppressive regimes,” Mr. Bush said, “because we know that the dissidents of today will be the democratic leaders of tomorrow.”

The president of the Reform Party of Syria, Farid Ghadry, said it was “wonderful” that Mr. Bush singled out Syria as a sponsor of terrorism and expressed his support for dissidents trying to bring about democracy there and throughout the Muslim world.

“President Bush is on the right side of history,” Mr. Ghadry, reached yesterday in Washington, said. “We moderate Muslims suffer as much from extreme Islam as anyone else, except we suffer more because we know our religion is a peaceful religion.”

President Bush also urged those who carry the banner of mainstream Islam not to allow fundamentalists to pervert it to justify violence. “The time has come for all responsible Islamic leaders to join in denouncing an ideology that exploits Islam for political ends, and defiles a noble faith,” he said.

As Mr. Bush explained America’s support for the worldwide spread of freedom, opponents wasted little time in dismissing his remarks.

Senator Kennedy, a Democrat of Massachusetts, issued a statement less than an hour after the president’s speech in which he labeled the remarks “foolish.”

“It is abundantly clear that staying the course is the wrong course for America,” Mr. Kennedy said, also faulting the president for speaking publicly about foiled Al Qaeda plots. “Such statements,” he added, “can only goad Al Qaeda into trying harder.”

A New York-based Iranian activist, Banafsheh Zand-Bonazzi, said yesterday that the president’s speech “gives people hope.”

The issues involved in bringing moderation and secularism to Iran, Ms. Zand-Bonazzi said, “must transcend the American anti-Bush clamor.”

“The masses in the Middle East seeking democracy and secularism find that this stance of the president, this language, and his constant hammering away at the issue is beyond helpful – it’s completely correct,” Ms. Zand-Bonazzi said.

Mr. Ghadry added that President Bush’s remarks were important in that they provided vital moral support to those in the Middle East who want to bring about reform.

“This kind of call will encourage them,” he said of the president’s speech. “I commend him for that.”