because I'd say bombing medical facilities (or threatening to do so), or shooting doctors are pretty good examples of terrorist behavior. So is lighting construction equipment on fire in order to scare a religious community.

I'm sure at least some of the people involved in such activities are "recruited" in churches. Where people are using religion to cause harm, religious buildings are typically involved at some point.

Of course, I think the building itself is MOOT. It's not like the mosques are some sort of special terrorist facility. They're just places where individuals can find Muslims. If you wanted to recruit muslim terrorists, wouldn't it be easier to go where they muslims are? Particularly if you are abusing Islam for your terror? You could ban all mosques, and there would still be centers of high Muslim density where recruitment would tend to take place over other locations.