The US could literally blow North Korea off the map using tactical nuclear weapons based in Japan, South Korea and at sea with the 7th Fleet. Or delivered by B-52 and B-1 bombers and cruise missiles. But this would cause clouds of lethal radiation and radioactive dust to blanket Japan, South Korea and heavily industrialized northeast China, including the capital, Beijing.
China would be expected to threaten retaliation against the United States, Japan and South Korea to deter a nuclear war in next door Korea. At the same time, if heavily attacked, a fight-to-the-end North Korea may fire off a number of nuclear-armed medium-range missiles at Tokyo, Osaka, Okinawa and South Korea. These missiles are hidden in caves in the mountains on wheeled transporters and hard to identify and knock out.
This is a huge risk. Such a nuclear exchange would expose about a third of the world’s economy to nuclear contamination, not to mention spreading nuclear winter around the globe.
A conventional US attack on North Korea would be far more difficult. The North is a small nation of only 24.8 million. Its air and sea forces are obsolete and ineffective. They would be vaporized on the first day of a war. But North Korea’s million-man army has been training and digging in for decades to resist a US invasion. Pyongyang’s 88,000-man Special Forces are poised for suicide attacks on South Korea’s political and military command and control and to cripple key US and South Korean air bases, notably Osan and Kunsan.
President Trump, a word, please: bellicose hubris, and subsequent threats, will not work here.
And the price of such a war on the Korean Peninsula, in blood, money, and nuclear contamination, will be both unimaginable...and irreversible.
What needs to happen, is for China to get North Korea back on board with a summit to hammer out a true peace deal to replace the armistice, with the quid pro quo being no US invasion of North Korea, and North Korea ending its nuclear weapons program in return.
Such a plan is simple, elegant, and logical, and precludes the need for any military action against North Korea.
You're welcome, Mr. President!! :-)