[biggerten]

Of course, that's one we know about. We didn't see this one until three days too late.

These things happen far more than people realize, meteors explode in the atmosphere on a regular basis.

If you are not familiar with the Tunguska blast in 1908 you should realize that such an event would wipe out any major metropolitan area. And it would be assumed that it was a nuclear blast.

The evidence would not bear this out, but by then it would most likely be too late, some sort of retaliation would have taken place.

Unless you believe that a politician could resist the enormous pressure to retaliate. Who is retaliated against wouldn't be a matter of prime importance.

[Bloody Sam Roberts]

If you are not familiar with the Tunguska blast in 1908...And it would be assumed that it was a nuclear blast.

I am very familiar with it. However, I don't believe it would be mistaken for a nuclear attack to the point where retaliation would be in order. Monitoring of possible missile launches and incoming atmospheric anomalies such as a meteor is sufficient these days for us to determine exactly what hit us.

[Drammach]

I have seen several comments concerning assumption of enemy activity in the event of an XT object collision.

I think the majority assume it will happen in the U.S..
But what if it happens in Russia? China? India or Pakistan?
I can pretty much assure everyone here, the Indians and Pakistanis will not take the time to determine whether the event was a nuke or an asteroid/meteor, etc.
They will assume "nuke", and reply accordingly, with their target being their closest enemy.

The destruction of a major metropolitan area anywhere on the planet will be a serious matter, not just physically, in loss of life, but politically, as it could very well initiate full scale nuclear retaliation.