No doubt China was watching this very closely. If things reach the point where B-52's drop free-falling nuclear weapons or launch nuclear tipped missiles against North Korea, China will quite probably intercept and shoot them down. China certainly has nuclear tipped surface to air missiles, just as we do. Personally, I think if the USAF attacks North Korea's nuclear sites, they'll likely use massive non-nuclear bunker busters. There are very large laser or satellite guided bombs that can take out even a nuclear missile silo, or nearly any other underground bunker. If ZOG uses nuclear weapons, the result will almost certainly be tens of millions of people dead when American cites are destroyed by airbursting Chinese nuclear weapons.  I doubt china would do anything. china's whole reason for supporting them is to keep them from spilling over into china's border as refugee's. if we're nuking them by the millions, that would be a favor to china.     but the bombing exercises are just a show of force. we probably wouldn't nuke them except as a last resort. although I would prefer we nuke them as a first resort, to send a message to all the other nations who would plan to use nukes, and to save possibly trillions of dollars in war spending.     china also knows that if they were to declare war on us, they would never get their money back. all ties would be cut, all debts would be voided. we would stop trade, and china's economy would suffer greatly, while our own economy would probably see benefits. the US has outsourced soo much, it would be a benefit to americans if trade with china was out of the picture. china however, relies heavily on foreign investments to maintain its economy.     the US can't afford to not take nuclear threats seriously. if it didn't respond to them, especially if we were actually nuked, then that would be a sign of weakness to the other vultures and invite more attacks. there's a lot of countries out there that would invade and raid america if they thought they had a good chance of succeeding.     china may be a world power, but it's not going to risk its own destruction for korea. if china was to try to nuke the US, we would retaliate in kind. they also know we have anti missile defense systems in place, which could possibly stop most or even every nuke they sent at us. hell, if there was a war with china, I wouldn't be surprised if most other countries join in against china, even if reluctantly. if the world had a choice between the USA or china as the sole world power, they'd probably pick the US. especially since after such a war, if china was the victor, the rest of the world would be subject to its totalitarian influences. every other country would essentially become ruled by china.     if korea attempted to nuke the US, even if we thwarted those plans before a launch, china's hands would be tied. they'd have no choice but to let the US have its way with korea. hell, they'd probably want to join in. china may be big, but its military isn't huge and its soldiers aren't experienced. the US however, has been cutting its teeth across the middle east for more than a decade. experience plays a big role in the effectiveness of an army, even with today's hardware.      see if north korea really intended to nuke us, they would have already. but countries like korea and iran wanting nukes isn't just about having a means for mass destruction. they seek to use the nuclear trigger as a bargaining chip for political and foreign negotiations. this is equally unacceptable, and countries that would develop nukes for leverage need to be sent a message.    for example, immediately after north korea made the nuclear threat, it made demands to south korea that it wanted a set of islands it believes is theirs (islands where they pre-emptively without provocation, attacked and killed south koreans just a few years ago), and that south korea needs to invest in north korea like they promised. but that promise came with a stipulation that north korea stop developing nuclear weapons.     instead, they built nukes anyways and are using the threat of it to negotiate. they're essentially trying to force south korea to give in to demands, without bringing anything to the negotiation table but threats. but giving in to such demands would only give north korea even more of an ego, and they would eventually demand more and more concessions from south korea. south korea would essentially become subservient to the north's whims. so giving the north what it wants under threat of nuclear attack, is not an option. you feed an animal, and it will come back for more.