Wednesday's terror attack was the largest ever carried out by the Sinai Province, Islamic State's Egyptian affiliate, since it began its fight against the government in Cairo some four years ago. It also marked the most painful blow suffered by the Egyptian military in its war on extremist Islamist terror, which it is bent on eradicating. It was a well-planned attack, carried out by dozens of ISIS operatives in northern Sinai, and the explosions and weapons fire were heard loud and clear in Israel. Amid concerns that ISIS may try to spread their attacks in the direction of Israel -...