People that would revolt are the starving troops(Remember that the current famine is the famine of troops, not civilians).
Can't be too sure as they can pass the blame i.e. on the sanctions.
People in North Korea are also very patriotic, don't think they will not revolt unless there are obvious signs of mistreatments by the regime.
Russia won't intervene because Russia is actually pro-ROK at the moment. This is why NK demanded to have Japan and Russia dropped from the six-party talk, because they felt it was really 2(NK, China) vs 4(ROK, US, Japan, and Russia) and dropping Japan and Russia would bring down the balance back to 2 vs 2.
I don't think that is the case or will be for the long run. Medvedev are trying to get on the good sides with the west for political support, can't say it will be the same when Putin returns in power. Knowing his background and the historical ties between Russia and NK, things might sway to the other side again. Moreover, Russia have never trusted the west and we've witnessed events such as the bomber flying over the region where America was having drills with Japan and the endless rounds of heated debates about the European missile shields.
China on the other hand cannot send in troops during an internal revolt due to the US and ROK pressures.
It is unlikely China will allow military mishaps to happen in and around its borders. So something will definitely be done should internal revolts happen in NK. Fact that both parties (China & US) are being very calculating when approaching and trying to address issues surrounding this region means neither parties will be sending any troops. With that being said, there is no guarantee that it will not happen should one party decides to intervene militarily (Unlikely for now).
You don't understand the dynamics of East Asia then. Russia isn't China's friend. To the contrary, the only country that Soviet planned to nuke was China, and it was Nixon's intervention that saved China from a nuclear holocaust. Yes, ordinary Chinese do not understand that the US saved China back in 1969.
I never said Russia was China's friend. We are merely political allies and business partners. Both countries support eachother politically and protects our mutual interests.
To ordinary Americans it may seem like America saved China at the time, but that is not the only side of the story. The truth was, America worked hard to contain and to prevent the spread of USSR's global influence. China was an important ally to have at the time and can wedge inbetween USSR and Southern Asia. It was a win-win for China and America. On one hand it prevented the pro USSR movement spreading across the rest of Asia (taking advantage of the warm relations with Vietnam and other neighbouring countries at the time) and on the other (like you said) it prevented USSR from pressing the button.
However, that did't stop the ongoing rivalry USSR had with America. Mistrust and grudges still exists on this very day. Hence the counter vetoes, snide political remarks and missile shield talks etc.
