I don't think so. As far as I am aware the Chinese have never had protectorates out side of what is currently China. Certainly nothing like the Romans or the British (Where the sun never sets).
I do not think we need to worry about China taking over the world, much less the US. They already own about $250 billion of our Debt. Japan owns over $600 billion It is not in their self interest to see us go down. That would be like you beating the crap out of a house that you own. What would be the point. Your only going to hurt your self. Japn and China and the rest are invested in the US. They want money, not us. Normally when someone makes an "investment" that person/entity expects a return on said investment.
Here is an interesting read on the issue.
US debt
Out of the $8 trillion we are in debt over $2 trillion is held by foreign investors. That's a quarter of our debt. If we go under, we will be taking the rest of the modern world with us with out ever firing a shot.
I think you are underestimating the power of money and over estimating the power of a gun. 100 years ago you might have been right. In todays world, national interest takes a back seat to money. Iran is number 3 in oil reserve.
Oil reserve chart
Do you really think Iran or any of the investors (oil companies) are going to risk billion of dollars? If Iran does something stupid (not saying they wont by the way) the world economy would grind to a halt. Saudi Arabia cannot make up the difference. By the way, Iran may hate us but they are still taking our money. Do you think oil from Iran is not flowing through your engine block? It probably got exported to Canada or Mexico and then ship into the US.
Iran produces 4 million barrels per a day. It's got to go somewhere.
Oil production/export/import chart
IMO, that's why everyone want the Iraq problem to go away and for Iran to just simmer down. No one wants Iran to get the Bomb but no one has a way to prevent it from happening either.
The second anyone drops a bomb (surgical or otherwise) on Iran, the price of oil through out the world will sky rocket to the point that $100 a barrel would look like a fire sale. If you want to cripple the world economy, knock your self out. This country much less the rest of the world cannot afford that kind of bravado.