Makes it easier to understand what you're asking.
Tech, yes. We already are on the verge of having vehicle-mounted lasers beyond prototype stages (and man-portable versions probably won't be too far behind), power armor is within reach if we can only solve the exoskeletal power issue (we can make it, it just needs to be tethered to a generator right now), and predictions of turing-test passing AI are at 2045-2050 (which will result in robots that appear to operate on human-level intellegence.)
International Relations, Possibly. Globalization has hit the point where it's generally a bad idea to engage important players in an outright war. The 2008 recession started in the US with a housing bubble collapse, which eventually caused the economy in other nations to be negatively impacted. Things will have to get a lot worse before it devolves into a "every (nation) for (it)self" state. But considering what's going on in the middle east, a prediction that Russia might loose centralized control over itself within the next 10 years (which will make their nuke stockpiles less secure,) possible dissolution of the EU, and petrolium/oil evenetually running out, it can easily go that way.
Nuclear War, Possibly. I'm fairly certain that if (most) nuke-capable nations were forced into a war with each other, the nukes would be the last thing they would want to launch. As in, "we'd rather surrender and sign a peace treaty than have to use these damn things." Only possible way I can see the nuclear holocaust happen is... well, basically conditions of a war escalates to the point where "surrender for a peace treaty" equates to "national suicide." We're not talking post-WWII Japan, we're talking post-WWI Prussia (which was essentially dismantled by the subsequent peace treaty.)