Although the US government has the world’s largest nuclear arsenal, the US and its people are still quite vulnerable to nuclear attack, by either state or non-state actors. From Richard Morchoe at antiwar.com:
On January 27, 2000 in an email during his 2000 campaign for the American presidency, the late Libertarian Party candidate Harry Browne wrote,
“Today we have a strong national offense (the ability to blow any country to smithereens) and a weak national defense (the inability to defend against any two-bit dictator who gets his hands on a nuclear missile). We should have just the opposite. When we do, we will have a much more efficient defense-with a much smaller cost & a much less complex system.”
583 days later, Browne would be vindicated for the first time, sadly so. Despite all the billions (it was only billions back then) spent on the American military, 19 men came to America and hijacked planes to destroy the twin towers of the World Trade Center in the capital of finance. They also attacked the Pentagon and were foiled in one other action. True, it was not with a nuke, but horrible enough.
Browne did not predict the events, but they happened as could have been expected. We had been intervening in places in a way that was not to the liking of the people there and some actors noticed that there was an opportunity afforded due to the strong offense/weak defense situation.
Because Osama bin Laden supposedly launched the idea in Afghanistan, we invaded that land as he was not extradited. We did not go there because the Taliban struck NYC, they didn’t.
No matter, we have been there ever since and no one really gives a reason. Some give a mealy-mouthed rationale, but no one tells us why the Republic will fail if we leave. On February 2, 2019, Scott Simon gave a soulful little monologue on NPR about how women’s rights was a reason, well, rationale, sort of.
In essence, it seems we are there because we’re there.