Now we know why Truman started a slide into failure after ending WWII.
To give credit where credit is due, Truman's State Department was fiercely against recognizing the State of Israel at all. Truman overrode nearly all of his advisers in doing so. When he didn't recognize Israel as its capital, he was (a) following a year-old U.N. resolution, and (b) acting at a time when it was still unclear what borders the State of Israel would ultimately wind up with. (The Israelis themselves started with a provisional government based in Tel Aviv.) The fault lies more with subsequent administrations which never acknowledged Jerusalem as Israel's capital even after the armistice divided Jerusalem between Israel and Jordan.