Because unless you understand how some of the international laws in other countries work, you'll realize that despite all the wacked things about U.S., it probably is one of the countries that offers the most stable legal and financial systems. Coupled with the plethora of lawyers and litigation, you have recourses if there is fraud or foul play. Countries like china will be the wild wild west for average investors. Good luck getting anything back if the government whimsicially decides they don't like you.

Also, everyone right now is probably think the same thing you are and rushing either into international funds and/or gold.  Iwould say this will push the prices of those instruments up beyond fair value, making domestic equity relatively cheap again in the long term. But that's just my contrarian viewpoint. I think the time to get in to international was 2 years ago.