North Korean leadership might talk a big game, but they're not stupid. If they were to actually try anything by striking first, most of the world would be against them, and they know it. So while they might say a lot of things about how they'll destroy us all, that's all it is: talk.
I believe the United States and the rest of the world should ignore North Korea. I believe that regimen is dead set on starving their population to death while brainwashing them to worship a dead leader as a God. There's nothing we can legitimately do about because China supports them.
North Korea is China's problem since the Chinese supplied the Kim regime with the technology to produce nuclear materials. Japan is also close by. The United States is far across the Pacific and needs to concentrate on things at home. If North Korea becomes belligerent, our armed forces can be there within hours from bases in Japan and South Korea.
Ultimately, there will be an missile launch that hits Japan, S. Korea, or Russia that drags us into a war. Pressure on China must be maintained to curtail North Korea's weapklon development. North Korea's has been blackmailing both S. Korea and China to give them money for food to feed their people while the government spends their GNP on weapons development and better living conditions for their elite. North Korea's only strength is perfecting more effective deliverable nuclear warheads to all its neighbors and the US to continue their blackmailing scheme. A real treaty, with their neighbors would undermine the Kim regime. So besides channeling more internal descent among NK's elite to overthrow the Kim regime, adding defensive weapons to counter any NK military invasion of South Korea, the US needs to wait it out and until better options become practical. There is the belief that China, to gain more influence, will perpetuate NK's weapons development to prove the US cannot protect Japan and South Korea, so these countries side with China as their protector rather than the US. China wants to gain greater influence. Trade makes the world go around and China has the edge now.
No, the United States should not ignore North Korea. North Korea is a fascist state run by a mad man who may be nuclear powered. As such, North Korea warrants a watchful eye. Since North Korea has issued many anti-American statements, the United States would be wise to keep them under watch.
No, I do not think that the US should ignore North Korea at all, and I think that they have a lot of power, and some dangerous weapons that if they sent to the US could make such a huge tragedy that it would take decades to get over it.