President Bush is defending his decision to try foreign terrorists before a U.S. military tribunal. Some Democrats say the Administration's new security measures violate civil liberties.

President Bush told U.S. attorneys that he is reserving the option of military trials for foreign terrorists because he says those suspects must not be allowed to use the liberties of the U.S. justice system to destroy American liberty itself. "Non-U.S. citizens who plan and or commit mass murder are more than criminal suspects. They are unlawful combatants who seek to destroy our country and our way of life. And if I determine that it is in the national security interests of our great land to try by military commission those who make war on America, then we will do so," he said.

President Bush will decide himself, on a case-by-case basis, who might face those tribunals. The trials have no right of appeal and can be held in secret. Mr. Bush says the tribunals will act with fairness and deliver justice. Far more, he says, than terrorists grant their innocent victims.

"Ours is a great land and we will always value freedom. We are an open society, but we are at war. The enemy has declared war on us," he said. "And we must not let foreign enemies use the forms of liberty to destroy liberty itself. Foreign terrorists and agents must never again be allowed to use our freedoms against us."

Officials at the Departments of Defense and Justice are already working out the details of the tribunals, including rules of evidence which critics say will be much broader than civil law.

Congressional Democrats are holding hearings on the implications of a series of tough new anti-terrorism measures. Democratic Senator Patrick Leahy said the Bush Administration is failing to respect the checks and balances that make up the U-S constitutional framework.

White House spokesman Ari Fleischer says the President welcomes Congressional oversight but has no need to seek Congressional approval for the military tribunals since he is granted those powers under the Constitution.

President Bush says there should be no doubt about his intentions that those who plot terror and those who help them, will be held accountable in the United States. In hopes of uncovering more evidence about worldwide terrorism, Mr. Bush is also expanding a program offering visas to foreign nationals who have information about terrorist plots.

"We're saying, 'Welcome to America. You have come to our country. Why don't you help make us safe? Why don't you share information with us? Why don't you help us protect innocent people, women and children and men? Why don't you help us value life? As you enjoy the freedoms of our country, help us protect those freedoms?'" he said.

Mr. Bush discussed what he called a "war-time reorganization" at the Justice Department, putting more agents on the terrorism case, giving investigators better training and new technology, and working more closely with state and local authorities.