The deadly terrorist attack on the Pentagon has left the famous building badly damaged. But the headquarters of the U.S. Defense Department is functioning.

The Pentagon is open and people are reporting for work, but it is anything but a day of business as usual. Perhaps the best way to describe it is as a symbolic show of the Defense Department's determination not to be seen as crippled by terrorism.

Because portions of the massive five-sided structure remain without power and cordoned off, many of those reporting for work have nowhere to go. Firemen continue to pour water into the immediate area where a hijacked airliner crashed in what was part of a coordinated terrorist strike that also saw New York's World Trade Center destroyed. The fires in the Pentagon have not been fully controlled and smoke is still rising into the sky.

As for the rest of the building - that is, the parts that are technically open - the smell of smoke still hangs in the air. I can tell you it leaves a bitter, acrid taste.

There is still no definitive word on the overall number of dead and injured. But local fire officials have told reporters the final death toll could be as high as 800.

The military, both here inside the Pentagon and at bases worldwide, remains on the highest state of alert.

U.S. fighters have been patrolling the skies and the Navy has dispatched aircraft carriers and other ships to help provide additional defenses for both Washington and New York City. The military is also heavily engaged in providing medical and other humanitarian support to victims of Tuesday's terrorist attacks.