The IDF has been entirely dependent on US and European armaments and funds for all of its battles, with the only exception being the '47 independence war. Since then, Israel has been a Western military-industrial client state. The current genocide is entirely funded by the US.
It seems foolish, because giving the defense industry a free subsidy via Israel annoys our Arab oil suppliers and our oil companies, but there must be enough corporate welfare to go around because the defense companies and the oil companies haven't gone to war with each other directly, yet.
Western Europe went through ~200 years of brutal religious wars from the advent of Protestantism. The same is going on in the Mideast, it just started only 100 years ago with the fall of the Ottoman Empire.