Peter, as Steve Metz has already said in another thread of yours:

A wise strategy is one where the expected benefits--increased security--justify the expected strategic costs (blood, money, lost opportunities). This does not meet that standard.
I would offer that you have gone to great lengths to ignore the reality that one does not focus on the MOST DANGEROUS course of action that any enemy may employ, but the MOST LIKELY. It is a time-proven measure that allows one to apply the resources at hand; whether it be at 10 diplomatic mission or 100 does not matter.

I could button an ambassador up in a 70-ton main battle tank to reduce the risk from a wide range of threats as he moves about a host country, but there are a host of other reasons why that approach would be neither practical or prudent. As the saying goes, "just because you can does not mean you should."

I will give it to you that you've applied a great degree of thought to your position. Are you related to anyone with the last name of Sparks?