From the Jihadis viewpoint, this was a very successful attack. I predict copycat attacks in the U.S.
Simple, done by a Jihadi of 1, requires almost no preparation. No chemicals to buy, no permits to obtain. Just rent or steal or buy a truck and go.
many Muslims drive OTR trucks here in the states.. Not saying all of them would plow in to a crowd of people..
but it only takes one.