Don't forget that after Al Qaeda's 1996 truck bombing in Dhahran, Saudi Arabia, that killed 19 U.S. servicemen, Saudi Binladin Group built military barracks and airfields for U.S. troops.
See eg Wall Street Journal article "Bin Laden Family Could Profit From a Jump In Defense Spending Due to Ties to U.S. Bank", Wall Street Journal 27 September 2001 -
http://www.globalresearch.ca/articles/WAL110A.html But above all, dont forget WHERE THE ANTHRAX CAME FROM.