I don't see how China could plausibly threaten the U.S. by 2007. From what I have read, the U.S. has WAY more nukes than China, in fact a lot more nukes than China and Russia combined. If it came down to flying nukes in the Middle East, the U.S. would settle that situation pretty quickly, by lobbing it's own into the mix. China and Russia could be kept at bay by simply reminding them that we had PLENTY of nukes left over to take care of both of them too, should the need arise.
Perhaps Iran would be crazy enough to lob a few nukes at Israel - but that would be their entire arsenal. However, I would imagine that Israel's response would equally devestate Iran, as I believe Israel probably has more nukes than Iran. In addition, the U.S. would probably "plant" a few nukes in Iran also. I think that would pretty much end any conflict for the time being. Any conventional military force fielded in the Mid East by China and Russia, should they choose to invade, would be taken care by more U.S. nukes if needed - the U.S. could not allow the Mid East oil to fall into enemy hands.
The only way I can see the U.S. "advantage" being countered is for China to build a LOT more nukes, so that the threat of retailiation by the U.S. becomes meaningless (back to the cold war again). However, if China started this type of nuclear buildup, the U.S. would begin doing the same, just like we did back during the time of the Soviets.
This of course is all built upon my original premise that the U.S. really DOES have a lot more nukes than everyone else combined (at this point in time, anyway). If I am wrong about that, then China and Russia might feel more emboldened, as outlined in this article. Otherwise, China is not not going to feel ready to move openly against the U.S. for at least another decade (and hopefully a lot longer - like NEVER!!).
My biggest fear with Iran is that while they are busy posturing out in the open, they will build a few nukes and secretly give them to al-qada (or however it is spelled!!). These would then be smuggled into the U.S. and detonated in a few of our large cities. Dealing with THAT would effectively cause us to retreat from the world stage for several years, at least. Which is what the Islamo-facists really want.
It would also make us so paranoid about our sea ports and imports that we would essentially stop importing all foreign goods for a REALLY long time, even though most of our nation would still be intact (not to mention that everyone in the U.S. would be in a panic to move out of the large cities, and everyone would be moving here and there trying to avoid living in the next nuclear target zone - even though there probably would be no "next nuclear target zone"). The net effect would be the collapse of the world economy. Then, all bets would be off!!
Of course, not all world leaders react in a predictable fashion, so anything could and would happen in reality. Let us all pray that cool heads prevail everywhere, and that NONE of this comes to pass.
If nukes went off in this country and we did not know who did it, this country would take out the nuclear facilities of all terrorist nations.
That would mean good by North Korea, Iran, and perhaps the nuclear facilities of Pakistan. I would expect a surgical strike on their nuclear facilities with tactical nuclear weapons. After we were hit we would have the "weapon signature" of the nuclear facility that processed the fuel for the bomb. Once the isotope mixture is analyzed we would know which nation did it. I would then expect a strategic strike against that countries military, civilian and industrial base with the intention of maximizing destruction and death. In effect the removal of the offending society from the face of the earth.
(Do not kick a sleeping tiger in the butt, it makes him angry and hungry)
Before you make predictions about how America would react to a nuking, consider what happened after pearl harbor. Then contemplate Hamburg, Dresden, Hiroshima, Nagasaki.
Probably, some Senator would get up and say "Arabia Delenda Est".