So essentially the ending is that everyone backs down, the status quo is restored, all the people who were hurt come back. The book definitely develops a Cold War theme. It often does so overtly such as the discussion of which world leaders worked for God/the Devil. So the ending is sort of a Cuban Missile Crisis, looks like things are going to get real bad but ultimately there's de-escalation. The fact that the crisis is averted is creditted to God's ineffable managment essentially. Both sides had their excesses but raising the anti-Christ in the country-side away from both sides influence ultimately worked out.
The big problem with this is that when the Soviet Union and the U.S. clashed but didn't directly go against one another, the people who died stayed dead. The telemarketers and the like aren't magically restored to life. Those world leaders supposedly working for either side, they kill people for real. That's just as true even if they're manipulated into serving some greater good.
Raising everyone that was killed delivers a feel good ending that undermines the rest of the book. I'm okay with the apocalypse not actually happening, that makes a lot of sense as the ending. But when you play games of intrigue, even if you play it very well, people still die. Heck, even if you ignore the genocidal parts of the bible civilians go down all the time. So by serving up a guilt free victory the book stopped being particularly relevant to the world we live in.
I still enjoyed it and will probably read it again some day. But it's a bad ending.