Really?
The GMD system has 44 interceptors in deployment at present, ready to intercept an ICBM-class target on 24/7 basis. Successful intercept of long-range ballistic missiles in two major tests (2014 and 2017) validate the claims that GMD system is up to the task.
North Korea is in the process of
testing its long-range missiles at present; there is a massive difference in
testing an ICBM and inducting it in large numbers which is impossible, given the state of North Korean economy. For example, Pakistan has
tested Shaheen-III ballistic missile in 2015 and it will not be mass-produced anytime soon (not even inducted yet).
North Korea's ability to strike US mainland with a nuclear warhead is largely suspect in the light of its technological limitations and budgetary constraints; chest-thumping on media notwithstanding. And this is a line that no country will dare to cross because US will "exterminate" the culprit in response.
Another thing is that Pentagon has amassed a great deal of
Intel about North Korean military and strategic developments through various means over time. If US will attack North Korea, objective would be diminish North Korean offensive capability ASAP with a large number of strikes on important targets with a wide-range of jamming techniques in the mix.
Chinese leadership has also informed North Korean leadership in secrecy that if North Korea dares to strike US territory, all bets are off.
Geopolitical situation is also different at present; China was largely independent of American investment in its economy in the 1950s but this is no longer the case. China is not welcoming a war between the US and North Korea but if it has to choose between the two sides, it will choose to side with the US due to cost-benefit considerations involved (terms and conditions apply of-course which are being negotiated as we speak).
Chinese leadership has also conveyed a message to North Korean leadership [in secrecy] that if it chooses to target US territory in the Pacific, all bets are off. This is why North Korea is very careful in adjusting the trajectory of its long-range missiles in recent tests.
Did you notice the trajectory of a long-range North Korean missile in a recent test? A large chunk of its flight was expended in space and distance covered on the ground was relatively short.
You think about these matters in black and white terms but reality is far more complex and American threats cannot be taken with a grain of salt. If they are serious about disarming North Korea, then the clock is ticking.
War is a terrible thing and it only invites death and destruction in the region. Millions might die in this conflict, Koreans mostly.
Misconception.
1. When North Korea invaded South Korea in 1951, US intervened and reversed this occupation effort (Battle of Pusan; Battle of Pusan Perimeter; Battle of Inchon). China saved North Korea from counter-annexation actually. Nonetheless, South Korea has progressed really well and is on good terms with the US since.
2. US closed the chapter of Manuel Noriega in Panama in 1990 (i.e. Operation Just Cause); Panama is on good terms with the US since.
3. When Iraq invaded Kuwait in 1991, US intervened and reversed this occupation (i.e. Operation Desert Storm). Iraqi military strength diminished consequently.
4. When Kosovo desired freedom from Russian-backed Yugoslavia in 1999, US intervened and Kosovo earned its freedom consequently (i.e. Operation Allied Force). Yugoslavian military strength diminished consequently.
5. US closed the chapter of Muammar Qaddafi in Libya in 2011 (i.e. Operation Odyssey Dawn). Libyan military strength diminished consequently.
6. US closed the chapter of Saddam Hussein in Iraq in the period (2003 - 2006). Iraq is in ruins unfortunately.
7. US closed the chapter of Al-Qaeda Network across the world in the period (2001 - 2011).
Victory implies
fulfillment of political objectives and/or
elimination of key opponents in the [target] region. US has achieved victory in majority of its wars throughout its history.
At present, US is on the verge of closing the chapter of ISIS across the world (i.e. Operation Inherent Resolve) and shifting its attention to resurgent Taliban in Afghanistan:
http://www.washingtonexaminer.com/u...y-long-winter-for-the-taliban/article/2643252
If Trump administration stay in power for long, US will succeed in Afghanistan as well.