FBI and Bombs

It was just May Day, and five guys were arrested by the FBI for attempting to blow up a bridge in Ohio.

The first thing that occurred to me was that they weren't charged with terrorism - whereas the guy in Oregon who tried to detonate a bomb at a Christmas celebration (same thing, no?) was charged with attempting to use a weapon of mass destruction.  What's the difference in these cases???  My bet is white guys versus non-white.

The other thought I had was that this is yet another case where the FBI works for months to set up a string to get people to try to blow up bombs.  It just seems that they're putting a lot of effort into convince people to buy bombs and then (attempt to) blow them up, as opposed to actually catching people who are making/detonating bombs on their own.  The FBI claims it's preventing countless terrorist attacks ... but it just seems like entrapment for the sake of good publicity.  Let's see them actually catch someone who has a bomb that they didn't get from the FBI in the first place.  That would be saving us from terrorist attacks.