Obviously our understanding of Gods Covenant has radically and fundamentally altered over hundreds of generations; it would speak poorly of us if it hadn't. Yet more than that, Christianity is more than simply Judaism, Mark II. In the sense of a Jewish, Christian and post-temporal epoch a kind of dispensationalism makes sense. What's bizarre is the idea Jesus would swoop down, grab all the faithful, waggle His finger at non-believers, then torment them on Earth for a while before formally judging them and casting them into Hell. That seems as unnecessary as it is vindictive. It also makes a true tribulation incomprehensible; if all the Christians are raptured before hand, who is warned against taking the Mark of the Beast? Is it as simple as La Haye and Jenkins' model of unbelievers "tribulated" into faith? Last I checked it was fear, not love, that had to do with torment. Even from a very literalist perspective on judgement and Hell, it makes a lot more sense to regard the Millenium as a period of "Christendoms" dominance followed by a gradual tribulation culminating in the Apocalypse, Christs physical return and a final judgement.

The Rapture though is one step beyond; the VERY little scriptural support for it is EXTREMELY vague and open to interpretation, which is why the US has been around longer than believe in the Rapture. It's another of those cases that raise the question of why God kept something so important such a secret for so long before revealing it to a few unremarkable people.

EDIT: I do note that Wikipedia quotes Justin Martyr thus on Millenialism in general: "I admitted to you formerly, that I and many others are of this opinion, and [believe] that such will take place, as you assuredly are aware; but, on the other hand, I signified to you that many who belong to the pure and pious faith, and are true Christians, think otherwise". And no one had to be called a heretic and executed (well, except Justin, of course. )