Not to worry.
The U.S.A. put an official embargo on any sales of arms to the Jews living in Eretz Yisrael prior to the outbreak of the War of Independence in 1948, but the Jews were nevertheless victorious.
There have always been a few righteous people around the world in positions of leadership who provided "under the table" military aid to the Jews, as did Czechoslovakia in 1948.
And today, there are so many hypocrites on the world stage, that some of the same nations publicly denouncing Israel in public forums and encouraging a new war in the Middle East are delighted at the thought of the huge profits to be made by secretly providing a "third party conduit" of embargoed supplies to Israel.
In the final analysis, we must do everything that we can, yet rely only on Ha'Shem.