WASHINGTON (AP) In remarks suggesting U.S. military retaliation for the terrorist attacks on New York and Washington, Defense Secretary Donald Rumsfeld told U.S. troops worldwide yesterday that "in the days ahead" they will be added to the long history of American military heroes.

"We face powerful and terrible enemies, enemies we intend to vanquish," Rumsfeld said in a videotaped message to all Defense Department employees around the globe.

"The task of vanquishing these terrible enemies and protecting the American people and the cause of human freedom will fall to you," he said.

Rumsfeld noted the U.S. military"s history of heroism.

"At the Pentagon yesterday, heroes were here again. I know I am speaking to many now especially those of you in the field, those of you who wear the uniform of our country who will in the days ahead also be called heroes," he said.

A text of Rumsfeld"s remarks were distributed by his aides at the Pentagon.

At a news conference, Rumsfeld told reporters that an American response must be "sustained and broadly based," though he did not refer specifically to military retaliation.

Tuesday"s attacks on the World Trade Center and the Pentagon, he said, were "the definition of a new battlefield."

"It is a different kind of conflict," Rumsfeld said. He spoke to reporters in a grave tone at a news conference in a Pentagon briefing room that still reeked of acrid smoke from the smoldering fires.

Sen. Carl Levin (D-Mich.), chairman of the Senate Armed Services Committee, expressed hope that the United States and Russia might take "joint action" against Osama bin Laden, the exiled Saudi considered the leading suspect in Tuesday"s attacks.

He said Rumsfeld and Russian Defense Minister Sergie Ivanov discussed the situation Tuesday. While that does not necessarily mean Russia would join a military action, "it gives me some hope (that) in any world action against bin Laden we would find support hopefully not just from our traditional allies in NATO, but also Russia," Levin said.

Meanwhile, a Navy aircraft carrier sailed into the waters off New York"s Long Island yesterday and other warships stood guard off the East Coast as the U.S. military remained on high alert against further terrorist attacks.

The Navy was preparing to send a hospital ship, the USNS Comfort from Baltimore to the waters off New York City to provide emergency medical assistance to the World Trade Center victims. It said the ship is expected tomorrow after taking on additional supplies today in Earle, N.J.

Smoke continued to billow from the area of the Pentagon where a hijacked American Airlines jet barreled into the building at full throttle on Tuesday, minutes after two other hijacked commercial jetliners sliced into both towers of the World Trade Center.

At his news conference, Rumsfeld said an estimate from the Arlington County Fire Department, which led the fire fighting effort, that as many as 800 people may have perished in the attack was "considerably high."

Rumsfeld would not provide an estimate, although reports from the military services indicated the toll might be closer to 150 mostly Army soldiers plus the 64 dead aboard the airliner.

Asked whether the Bush administration was prepared to take bold action against the perpetrators, Rumsfeld replied, "Time will tell. I"m kind of old fashioned. I"m inclined to think if you"re going to cock it you throw it" in other words, if you threaten to retaliate you must carry through.

"So my instinct is you go about your business and do what you have to do," he added. "Anyone who thinks it"s easy is wrong. I think it will take a sustained and broadly based effort."

Secretary of State Colin Powell said President Bush was determined to punish those behind the attacks.

"We will find out who is responsible for this and they will pay for it," he said.

In a show of solidarity, the NATO alliance declared yesterday that the terrorist attacks in New York and Washington can be considered an attack on the whole alliance provided it turns out they were directed from abroad.

The decision grants the United States backing from its 18 NATO partners for military action, NATO Secretary-General Lord Robertson said.

It was the first time this solidarity principle has been invoked in the 52-year history of the alliance.

In addition to the aircraft carrier USS George Washington standing watch off Long Island and the carrier USS John F. Kennedy at an undisclosed location further off the East Coast, the Navy was moving several cruisers and destroyers out of port in Norfolk, Va., headquarters for the Atlantic Fleet.