Wow, Scafool, how'd we make it on to the same page all of a sudden?

The threat will manifest itself differently and for different reasons based on the target audience. It would be difficult if not impossible to defend a church like ours from an organized politically or socially based attack, but fortunately our church is not a relevent enough target for such a thing at this point in time. Not enough return on investment for such an attacker to hit a church when there are schools, courthouses and the like that are much higher profile.

BTW, we too have two sets of doors, the threshold door at the foyer and the interior doors into the sanctuary, and both are manned by greeters/ushers. If I were to train them, it would be to get as intimate as possible with new faces; the idea being that those with alterior motives will tip their hands easier if confronted. In other words, getting up close and personal with someone who has an agenda for attack will most likely force them to give away a tell as to their intention. As you say, facial expressions, willful disengagement, nervousness, anxiety, all are reads that tell the observers there's something there that warrants due diligence. So I think our lines of thought now are congruous.

I also expect that Sunday morning collections might become a bigger prospect for the desperate. One thing that thwarts this notion is most folks nowadays are writing checks for collection than dropping cash. If someone were to case our church and notice that most of the paper in the trays is not legal tender, I expect they'd seek fortune elsewhere.

To some extent, we are making use of the inferential intel and opportunistic contact our greeter staff use to give our latent forces a bit of a heads up, and yes, it is inadvertant on the greeters' part. Good call.

If the bubble does ever go up, I expect Churches will be a rallying point for many. For this reason, we do keep a cache hidden at church that no one else knows about.