Bush may call up 50,000 reserve troops

President Bush, pouring over options for war, may call up 30,000 to 50,000 members of the National Guard and Reserve to active duty in the next few days, a defence official said.

He said those called up would be used for defence duties in the United States.

The last such partial mobilisation by a president was in January 1991, when 265,322 reservists were called up for the Gulf War.

A full mobilisation of all 1.2 million reservists requires a declaration of war.

The military strike options go far beyond the short-term cruise missile assaults of years past in Afghanistan and Sudan and isolated air strikes against sites in Iraq.

Instead, they involve the potential lengthy use of military forces on the land, at sea and in the air.

Options include the covert insertion of elite special forces and long-range bomb strikes from manned aircraft, said senior military and administration officials.

In the most explicit description yet of the Bush administration’s intentions, Deputy Defence Secretary Paul Wolfowitz said the retaliation would be continued until the roots of terrorism are destroyed.

‘‘These people try to hide. They won’t be able to hide forever,’’ Wolfowitz said.

‘‘They think their harbours are safe, but they won’t be safe forever. One has to say it’s not just simply a matter of capturing people and holding them accountable, but removing the sanctuaries, removing the support systems, ending states who sponsor terrorism.’’

Navy Secretary Gordon England said: ‘‘This is not going to be a short programme.’’

The huge number of dead and the vast destruction wrought by Tuesday’s strikes has caused a different mindset to take hold among senior Defence Department officials, a ranking military official said.

‘‘If you are really going to do war, you do it with all assets political, economic and military, and that’s what they want to do,’’ the officer said.

Defence Secretary Donald Rumsfeld said combat planes will continue to fly over the New York-Washington corridor.

Appearing with England in a Pentagon briefing room still reeking of smoke, Chief of Naval Operations Admiral Vern Clark pointed out that the Navy already has two aircraft carrier battle groups, each with 75 warplanes, near the Arabian Sea.

That is twice the usual number for that part of the world. The USS Enterprise had been due to return home after being relieved this month by the USS Carl Vinson, but it was ordered to remain in the area indefinitely.

Such battle groups normally include cruisers and submarines, which can be launch pads for long-range cruise missile strikes, perhaps a prelude to attacks by manned aircraft such as B-2 stealth bombers or B-1 Lancers.

There were no other indications of a buildup of American forces in the Middle East or elsewhere.

Neither Wolfowitz nor other defence officials hinted at when the United States might begin military strikes. Bush said he would be patient.