But Dan, you're still thinking like a time traveler. I'm not talking about a traveler - I'm talking about somebody off the timeline entirely.
God doesn't need to come in and fix something after something has gone wrong. It's all part of the creation of the whole thing. This gives him the ability to fine tune everything as he's making it. He didn't create the universe a long time ago or in the future - those mean nothing. He simply made it, independent of our time, and in the process can reach in and adjust anything along any timeline. He doesn't wait for it to go wrong - it's already in need of fine tuning while he built it.
As for future people coming back and changing things...
If a person in the future reached back and changed a lottery result, then he'd never have to change the result because it will have already come up the way he wanted it.
You know for certain that you'll never go back and make an armored car crash near you last week and dump money all over you because if you were ever going to do that then an armored car would have already done so last week. Maybe it already did crash and dump money on you but you'll go back and keep that from happening because the money brought you nothing but grief, so you've already robbed yourself of the chance for free riches.
Just because you can change the past doesn't mean that you can ever know that the past has been changed. And anybody who changes the past will cease to exist and will be replaced by whoever they became as a result of the change. (Actually whenever somebody changes the past the entire universe would cease to exist and would be replaced by the Universe it became as a result of the change.)
From that standpoint, it could be argued that nobody in the future will ever change the past, because anybody who ever does will not exist when the time comes that they do it. "Hey, look, that die rolled and came up with a 1. I'm going to change it so it came up with a 6." That person will never see the 6. The person who does see it won't know that the result was altered because it wasn't altered - it always came up as a 6. In the timeline where it came up as a 6, nobody goes back and changes it.
One interesting facet to this would be a message transmitted from the future. The sender, having no memory of the message being received, would send it. He would then be replaced by a person in whose world the message WAS received and therefore would never need to send it. (And if he did anyway, then he would be replaced by a person who still hasn't sent it but remembers it being received twice.) The Universe where the message was received would go forth from that point, never to have the message sent. So any message we receive from the future would, by definition, never actually get sent. These would be messages that were never written, from people who will never exist. So, they were never sent even though they were received. Therefore, even if we receive messages from the future, we can still say that nobody will ever send one.
We may build working machines that let us change the past in any way we want, on any scale, at any time, at will. But we'll never, ever use that capability.
Maybe some future practical joker is responsible for getting George W. Bush elected. God knows he shouldn't have been able to do it without some kind of assistance like that. But, now that he's elected, nobody will ever have to arrange for him to get elected. The people who would no longer exist. (And good riddance.)
w
