President Bush says he is optimistic that Iraq will succeed in forming a government of national unity, despite sectarian violence following this week's bombing of one of the holiest sites in Shia Islam.

George Bush addresses American Legion members Friday

President Bush says the enemies of freedom in Iraq are working to stop democracy because they are scared.

"They understand a democratic Iraq will be a major defeat in their totalitarian aims," he said. "They are going to continue their campaign of violence and destruction."

Mr. Bush says the world saw the terrorists' brutality in Wednesday's bombing of a Shi'ite shrine in Samarra, which set off a wave of reprisals that killed more than 200 people.

The president again condemned that bombing, saying it was an affront to people of all faiths. He vowed to help bring those responsible to justice, and repeated calls for calm.

"Many religious leaders are committed to a unified Iraq, a peaceful Iraq," he said. "The response by the Grand Ayatollah Sistani and many other leaders has been constructive and very important, and we appreciate their leadership."

In a speech to U.S. military veterans, Mr. Bush said, this is a moment of choosing for the Iraqi people, and a time of testing for Iraqi security forces, who he says, U.S. generals report are doing a fine job in enforcing curfews and working to restore order.

"We can expect the coming days will be intense," he said. "Iraq remains a serious situation, but I'm optimistic because the Iraqi people have spoken."

He says they spoke by participating in December elections, sending what he says was a clear signal to the world and to terrorists that they want freedom and democracy.

The president says forming a government from those elections will be a difficult and exhausting process. He encouraged politicians to reach out across religious and sectarian lines to build a government of national unity.

Once established, that government will face tough decisions on security, reconstruction, and economic reform. Mr. Bush says it will need to earn the confidence of the Iraqi people by showing it can protect them from terrorists, by putting a stop to human rights abuses by security officials, and by protecting minority rights.