If the US economy collapses, an I mean *really* collapses, not like this faux doom and gloom in Europe, then it's probably going to be pretty lousy everywhere on the planet.
it wont collapase, but the slow slog towrds a diminishing way of life has begun.
IT WILL GET WORSE BEFORE IT GETS BETTER.
The way out of it is not a 401k. The governments in other cash strapped countries have raided similar programs to pay for themselves. The best way is to hedge EVERYTHING. Diversify to the max. Assets, currencies, equities, etc. Do it in multiple countries, and dont put more than couple eggs in any 1 basket.
To answer someone else, I am a biological oceanographer that does both research for Governments and consults for the fishing industry, as well as statistical consulting. I can work anywhere there is a coast.