Neither side was heavily armed. The Arab forces were better armed than the Israelis, and by a fair margain, but both were mainly small arms. The best force in the region was the Arab Legion, which was well equipped and consisted of two full brigades plus smaller formations, including armored car companies, and was very well trained and commanded by experienced British officers. The Egyptians were very potent on paper, but most of their forces were poorly trained.
If the Israeli militias, many of them fresh out of the refugee camps, had broken, or if the Arab Legion had been given an unlimited AO, instead of being held mainly in check by the Jordanian king (who main wanted to ensure his territorial desires were in hand), it could have gone quite badly indeed.