I don't know. Prior to Timothy McVeigh anyone could buy a truckload of ammonium nitrate, no questions asked. I guess it was inconceivable then that someone would, or could use a truckload of it to build a truck bomb. Now you can't buy two fifty pound bags without a phone call or a visit to inquire about what you're going to do with it. Most of the rocketeers I know that use it to make rocket fuel, get a visit instead of a phone call. They keep pretty good tabs on it now.
The japanese used kamikazes quite effectively in World War II so suicide missions using planes as missiles should be no surprise. Should it have been expected or anticipated though? In hind sight it is easy to say yes but can you really put yourself back in time and try to answer that question in foresight?
It would seem to me that gasoline tankers could be used pretty effectively as weapons too. It's pretty easy to find one running with the keys in the ignition and the doors unlocked at many truckstops across the country as the driver takes in a meal. Should we expect that at some point someone may try to use one or more of these trucks as weapons?
A bunch of terrorists highjacked a few planes and the airline industry has been locked down. A simple pair of fingernail clippers can get you run thru the wringer to make sure you're squeaky clean. Timothy McVeigh used a rental truck to take out a federal building. Several times I rented a truck since then and not once has anyone asked what I was going to use it for. There's been no noticeable change that I can tell regarding the security of rental trucks.
It scares me that I can think of many simple ways that terrorists could take the next 100 or 1000 lives and I'm just an ordinary citizen with no guerilla training. What methods could trained terrorists think of? Should we be able to anticipate them? I don't think we necessarily can ![]()

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