Terrorism is a headache

The US Consumer Product Safety Commission (CPSC) is trying to ban the sale of various chemicals to people who don’t have an explosives manufacturing license from the Bureau of Alcohol, Tobacco and Firearms (ATF). Fair enough, you might think—unless you know enough chemistry to recognize some of the substances on the list. Aluminium powder, for example. Am I wrong to think that a terrorist will be smart enough to work out that given the softness of aluminium, you can use a bar of aluminium metal and a grinding wheel?