That seems like conventional wisdom, but the U.S. started a large military build-up before Pearl Harbor. The military draft began in 1940. And of course the U.S. was actively supporting the UK through lend-lease.

There were still isolationists in Washington and even prominent supporters of Hitler in the public sphere (if you ever wonder how misguided people can be, remember that), but certainly there were many indications that the U.S. would enter the war.

But, until Pearl Harbor and the Philippines there was no clear pretext for the US to declare war. And had they not attacked, it's not clear that FDR could have gotten congress to declare war. Some of those prominent supporters were significant industrialists like Ford, they would have fought intervention by all means.

After Pearl Harbor, there was no debate.

Maybe the first and third were seen as necessary to protect a neutral country? Or being short of declaring war, they were less objectionable? But I'm just guessing ...

Lend-Lease had fairly staunch resistance, as it basically shredded any pretense of neutrality. The draft and the military build-up were supported in large part due to neutrality--the need to have a sufficiently strong military to deter potential aggression (this was the strategy of Switzerland). When FDR extended the draft term from 12 months to 18 months, it passed by a single vote in the House.

But, yes the US had a constant stream of arms being supplied to Britain and Russia during the period before the war.

I always akin it to tag team wrestling. The first guy beats the other team almost silly, then tags out and the fresh guy comes in fresh and finishes them off.

If only USSR didn't enter WW2 on Hitler's side...

... You mean apart from the Indian wars which annexed territory, the Mexican-American war which annexed territory, and the Spanish-American war which annexed territory? Then there was the War of 1812, where the US tried and failed to annex Canadian territory. Or the Barbary wars.

The US not wanting to involve itself in internal European wars does not mean it was militarily isolationist. The US has been projecting military power beyond its borders pretty much since its inception. Military power projection is in the US's DNA, not isolationism.

I mean, how do you characterise sending warships to scare Japan into opening up for trade in 1868 as 'isolationism'?

George Washington's farewell address addressed this:

"The great rule of conduct for us, in regard to foreign nations, is in extending our commercial relations, to have with them as little political connection as possible. Europe has a set of primary interests, which to us have none, or a very remote relation. Hence she must be engaged in frequent controversies the causes of which are essentially foreign to our concerns. Hence, therefore, it must be unwise in us to implicate ourselves, by artificial ties, in the ordinary vicissitudes of her politics, or the ordinary combinations and collisions of her friendships or enmities."

Thomas Jefferson said that one of the "essential principles of our government" is that of "peace, commerce, and honest friendship with all nations, entangling alliances with none."

Monroe:

"In the wars of the European powers, in matters relating to themselves, we have never taken part, nor does it comport with our policy, so to do. It is only when our rights are invaded, or seriously menaced that we resent injuries, or make preparations for our defense."

Seward:

"defending 'our policy of non-intervention—straight, absolute, and peculiar as it may seem to other nations'...[t]he American people must be content to recommend the cause of human progress by the wisdom with which they should exercise the powers of self-government, forbearing at all times, and in every way, from foreign alliances, intervention, and interference."

Here's a Wiki on it: https://en.wikipedia.org/wiki/United_States_non-intervention...

You seem to be arguing that the US projects military power in it's own interests. That's undeniable, but claiming that as a counterpoint that we weren't isolationist in the 19th century is not what isolation means. For recent examples: invading Afghanistan was for our own interests; we were attacked by a group sheltered by their government. Iraq was not. Syria is not. Balkans in the 1990s was not. Panama was because of the canal and trade routes. WWI and WWII ultimately was in our best interests but it wasn't obvious at the time, particularly early on, and the cost was immense. Right now, we are so intertwined in alliances that if just about any country goes to war outside of sub-saharan Africa, we are automatically at war.

And despite you quoting several people including terms like "forbearing at all times, and in every way ... intervention and interference", I have already furnished you with more than a few examples of the US actively intervening and interfering. The US not only meddled a heap in the Americas, but also outside it's own area (like the Philippines and Japan, already mentioned). Neither does 'non-intervention' square with things like backing Cuba in a war of independence against Spain. That's the living, breathing definition of 'intervention'.

You seem to be missing my point that the US was politically isolationist with respect to Europe, but it wasn't isolationist outside of Europe.

> Afghanistan was for our own interests; we were attacked by a group sheltered by their government. Iraq was not. Syria is not. Balkans in the 1990s was not.

This is all total propaganda. Iraq was 100% in the US's interests (or perhaps better put, the incumbent government's interests), and the US fabricated a casus belli to invade, against the wishes of its allies, and with no quality intelligence. Syria is a leftover from the Iraq debacle; the US would lose considerable international reputation if it just shrugged and walked away from the consequences of the clusterfuck it caused in Iraq. There was no alliance requiring that the US invade unilaterally in the case of Iraq, and the consequences of that populist action are now tearing Europe apart. There is more to national interests than conquering territory and acts of military revenge.

If the US got itself involved in conflicts that weren't in its interests, then it'd be much more involved in sub-Saharan Africa. Or filling eastern Ukraine with gung-ho marines and reverting the annexation of Crimea. I don't expect any nation to act against its interests, but if people are going to persist with the myth that the US really is the 'world cop', then it's a corrupt cop who looks the other way when there's no kickback coming its way.

...and even then, it wasn't entirely clear that the US would enter the European war, until Hitler declared war on the US.

Prior to US involvement, the front line was quite close to Paris. After, it was just over the border of Germany, and then as you said, they knew it was over. US' involvement was huge.

Britain. Along with contingents from most of its Empire.

(Saying "England" when you mean "Britain" is like saying "Texas" when you mean "U.S.A.")

On the contrary, I think it is exceedingly likely that the US will always intervene (if it has the capacity to do so) if a single military power looks like taking over most of Europe. It's why the US intervened in both WWI and WWII, and created NATO.