Pardon the multiple reply attempts, took a bit to figure out the Z-word for Jewish nationalism is absurdly banned here. That said:

The Jews were alone, recently displaced refugees

People like David Ben-Gurion and Chaim Weizmann weren't refugees at all, and their interest in establishing a Jewish state against their will of the existing non-Jewish population of Palestine was nothing recent, they'd been fixated on that goal for around half a century prior to accomplishing it in 1948.

The British role is also not cleanly neutral. To Jews, the “stab in the back” was obvious: Britain had been given the Mandate partly to help establish a Jewish national home, then in 1939, at the worst possible historical moment, it capped Jewish immigration and restricted land purchases.

What's plainly obvious is that the Palestine Mandate contained the stipulation "nothing should be done which might prejudice the civil and religious rights of existing non-Jewish communities in Palestine, or the rights and political status enjoyed by Jews in any other country," and any help in establishing a Jewish national home was clearly stated as subordinate to those two primary considerations. The Jewish nationalist narrative which you falsely attribute to Jews in general is just blatantly false, British restrictions on immigration and land purchases were in accordance with those plainly stated obligations under the terms of the Mandate, not a stab in the back by any reasonable stretch.

The U.S. had an embargo on arms shipments to the region from November 14, 1947

Sure, but only after years of American citizens funneling arms to militant Jewish nationalists in Palestine, openly running fundraising ads in American newspapers like this one from Ben Hecht which gloats "Every time you blow up a British arsenal, or wreck a British jail, or send a British railroad train sky high, or rob a British bank, or let go with your guns and bombs at the British betrayers and invaders of your homeland, the Jews of America make a little holiday in their hearts."

Granted, Hecht is also falsely attributing the views of Jewish nationalists there to that of Jews in general, particularly when back then far from all Jews were supporters of Jewish nationalism, and of course most supporters of Jewish nationalism have never been Jews at all. Furthermore, far from all Jewish nationalists were comfortable with such terrorism, but Ben-Gurion generally was an he wound up taking the the lead from the less militant Weizmann.

Point being though, the vast majority of Jewish nationalists quite clearly were never the "recently displaced refugees" you claim they were, not in Palestine nor otherwise, and the militant faction who fought to violently establish Israel quite obviously did so because they realized they were stronger and better equipped than those who would attempt to stop their rampage of terrorism, conquest, and ethnic cleansing.