Was the US justified in removing the Taliban from power in Afghanistan?

[Don Corleone]

I'm afraid a discussion of the French presidential race is not an appropriate place to have this discussion. So here we are, another war debate.

Now, on October 14, 2001 the USA and our allies launched an aerial invasion of Afghanistan. Several days later a ground invasion began as well. The stated goal was to remove the Taliban from power, to shut down Al Queda training camps and to capture and put on trial Osama bin Laden; for the 1998 embassy bombings, for the 2000 bombing of the USS Cole and the 2001 9/11 attacks in which almost 3000 Americans were killed.

Shortly after September 11, 2001, President Bush announced to the world an ultimatum to the Taliban, that if they did not surrender Osama bin Laden, they would be viewed as supporting and sheltering him and would be treated as such. The Taliban's response? They refused to acknowledge the statement. Speaking to Saudi and Pakastani ambassadors, they claimed to acknowledge a non-muslim leader of any country would be an insult to Islam, and that only muslim heads of states where sharia was enforced were legitimate rulers.

After several weeks of stall tactics, during which Saudi Arabia and all other states, save Pakistan, severed diplomatic ties with the Taliban, the USA's deadline expired and war commenced.

Was the USA justified? Note, for the purposes of this thread the subsequent military actions in Iraq are not open for discussion, except in how they can be linked to the original decision to engage the Taliban with military force.