What would be the consequences, and how do you think the world would develop thereafter?
The hypothetical:
Over the next 5-10 years, American public opinion turns against a vigorous global role for the US. People tire of the constant stream of news about NK/Iran/Russia/China/terrorism and say a collective "f it."
Eventually, politicians who desire a global role for the US must make a decision: retire, or change their positions.
The parameters
The US remains a NATO power and will honor Article 5, but withdraws all troops from Europe
The US remains in the UN, but cuts its financial contribution in half, and abstains from most Security Council votes unless they directly impact the 50 states/territories.
The US tells Israel " You're on your own. We won't help
or hinder you in any way."
The US leaves the WTO and all existing free trade agreements with 2 exceptions: NAFTA ( which is heavily renegotiated) and a bilateral agreement with the UK. A 40% tariff on all other imports is enacted.
The US continues to vigorously develop its own energy sources ( green and otherwise) to achieve full energy independence, and leaves the Middle East entirely to its fate.
In the Eastern Pacific, the US tells SK/Japan/Phillipines/etc " We're no longer interested in the burden of defending you. Look to your own defense." The extent of US influence in the Pacific is a line from Hawaii to Midway to Alaska.
By the end of this, no US troops are to be found outside the 50 states/territories other than the US Navy.
The US maintains its current level of military spending, but now solely focused on the defense of North America.
So, how would subsequent events go?
@
Skroe , I know this is anathema to you, but you have said before that if US public opinion turned against a global role for America and decided on our own "East of Suez" moment, it would of course happen that politicians would either go along or be out of a job.