Let’s see: Three barbecue-grill propane tanks, a bunch of M88 firecrackers, a couple of plastic gasoline cans, some non-ammonium-nitrate (meaning, non-explosive) fertilizer, and a couple of alarm clocks — a big mess, and a frightening one, but nothing that was actually going to blow up. As is often the case, the United States of America has great luck when it comes to our enemies. The people behind the Times Square bomb obviously lack the technical sophistication to be much of a threat. It is very likely that they will be caught and dealt with in the appropriate fashion.
On the other hand, we should be mindful of this: The main reason that we do not have an intifada of steady, low-level, low-tech attacks — real car bombs on Times Square, shootings in the shopping malls — is that al-Qaeda does not do things that way, preferring terrorist spectaculars and coordinated bombings. But al-Qaeda does have the technical know-how to make a car bomb. So do its affiliates and allies.
There is no reason that the guys who build the IEDs in Iraq and Afghanistan cannot build them here — except that they are there and not here. The main thing to do is to keep them there and not here. Every day that we do not gain real control of our borders, or (especially) get a better handle on our visa process, we invite somebody who does know how to pull off a Times Square bombing to do so. We were lucky in our enemy this time. We aren’t always lucky.