Of the first four articles linked above, three do not mention the US at all. The fourth says only that the US expressed concern about security and offered to provide an aircraft carrier nearby.

I got too bored with the flames to look at the other links, but the four I did look at were essentially IDENTICAL (with no credit to an original source). The only OBVIOUS conclusion is that plagiarism is acceptable in UK news media(?), which is hardly a surprise but not exactly an end-of-the-world discovery.

Depending on the kind(s) of missiles used, most can be, and usually are, set to "explode" or to "inert" themselves if they fail to hit a target**, so the danger to those on the ground is more akin to getting hit by a falling bathtub (or "porcelain throne") than of being blown up. I think I'd rather be in the vicinity of manned intercept aircraft, but it's pretty much a Brit decision on their home turf.

** many homing missiles have been designed to explode if "miss distance" begins to increase, on the assumption that "if it ain't gonna be a hit" blowing it up might still take out the target. All the missiles of significant potency that I've seen details on (admittedly not the latest stuff) have included self-destruct or inerting provisions. You have to almost deliberately hit the wrong target to be a real hazard to the innocents.

John