Shorthand.
The USA and China have diverging interests in several areas (in some respects with North Korea, in some respects with Iran, international boundaries in sea lanes, etc.) The USA and Russia have diverging interests in several areas (in Syria and before that in Libya, natural gas, press and NGO freedom of operation in Russia, etc.)
Yes, all countries have diverging interests, but it's a little more intense in those two cases. "Adversaries" may be too strong, but there is a great deal of tension in the relationships even if we don't come to blows.
"If you owe the bank $1000, the bank owns you. But if you owe the bank $1,000,000, you own the bank." ;-) China needs to buy US bonds more than the US needs money from China - http://www.guardian....conomy-china-debt
I think my arguments about Snowden's actions have been a bit more nuanced than your last paragraph, but readers can make up their own minds. I won't punish everyone by trying to go through them again. :-)
Cheers,
Scott.
