Is a war pitting the U.S. and its allies against nuclear-armed North Korea on the horizon?

While most analysts, regional security experts and government officials say the odds of conflict erupting on the Korean Peninsula remain low, observers say there has in recent months been a noticeable but discreet uptick in not only heated rhetoric, but also in military preparations by the United States as well as moves by Japan to limit the fallout from any potential conflict.

As Seoul and Pyongyang continue to lay the groundwork for rare intra-Korean cooperation in next month's Winter Olympics in Pyeongchang, South Korea, the U.S. has quietly been deploying an assortment of powerful weapons — what it calls "strategic assets" — to the region. The military has sent nuclear-capable bombers, including three stealth B-2s and six of its workhorse B-52s, to the U.S. territory of Guam, a key logistics hub and outpost some 3,400 km from North Korea. Those planes join six B-1B bombers, which like the others would likely play a critical role in any strikes originating from Guam on nuclear, missile and leadership sites in the North.