In a time like that I would probably be coming from somewhere in the world having just spent some time working for some big company on my way home to help with the family business.
At that point I would probably be an accomplished engineer with a few major projects under my belt and a capable leader.
If I was called for Japan I would probably go. I actually know my way around the major cities having gone there twice in my teens. I'm not sure what I would be completely be capable of at that point but I think that if there is a big problem, they're going to need every helping hand.
Among the things that I am sure I would be capable of is to ask help from my own country, the Philippines. Being a country relatively close to the Philippines, I would be able to call in people to bring in some sort of relief goods among other things.
Of course, I myself would be taking a trip there to meet up with everyone else, I'm not sure what I would do alone, but if we all got together, I don't think even God could withhold a miracle.