You may fully understand why foreign individuals or businesses owning U.S. assets doesn't create a problem for us, but what about when foreign GOVERNMENTS do? (By the way, this may be a good time to highlight that everything we're learning applies to other countries. You could replace the "U.S." in the previous sentence with French, Russian, Brazilian, etc. We're studying the effects of globalization with reference to domestic and foreign effects. Talking about the U.S. is just shorthand for "domestic.")