Wouldn’t sending Big Bird out and about showing no call sign kind of mark it as a bit of a target? It’s not like the muzzards can’t get their hands on an RPG or two?
This is a special conundrum.
MIL call signs are assigned by Air Command; in POTUS case, Air Command at JFB Andrews.
You’d think he doesn’t fly with the AF1 for security reasons.
Yet none of his predecessors were worried when over CONUS and flew with it (almost) every time; here he has \never\ had it assigned.
What is it that MIL Air Command understands here?
And, his itinerary is available on the webz while he flies around in a big (737/747/757) blue and white airplane that everyone can recognize.
What you say, “...kind of mark it as a bit of a target” has it’s own reasonable conclusions that include, the military is not flying escort per protocol.
There are other “data points” that say the same thing, BTW.
In the end, what does it mean?
Who is on that plane?
What is that person’s relationship to the military?
Logical conclusion is...