It was hardly a miracle. The Israeli military was much better trained and many were veterans of World War II. They were fighting on interior lines. Except for the Arab Legion, the Arab military was untrained and poorly equipped, and often fighting each other as well. The British Empire (whom we did defeat, we only fought the Arabs to a stalemate – that continues) were collapsing and had recently been evicted from India and were shortly to flee most of their other overseas territories – they were bankrupt and actually quite happy to give up rather than fight for their empire.
One should note that in Jewish tradition, victories over goyim are never celebrated. That’s why we don’t say Hallel on the last days of Pesach (and that was clearly a miracle – we weren’t even armed). For Hanukah we say we are saying hallel to honor the miracle of the menorah buring, not in honor of schechting the Greeks and the Misyavanim. But of course, how do those compare to 1948? What’s Moshe Rabeinu compared to Moshe Dayan? Who would want a Makacabee if you could have a Palmalnik? Note that the vast majority of Jews living in Eretz Yisrael in 1948 observed things first hand, and only a small minority thought a miracle had occured (you wouldn’t catch Ben Gurioun saying Hallel – if there had been a miracle, wouldn’t he have known about it).