The death of more than 100 Palestinians and the wounding of hundreds of others in the six-day-old Gaza war were not enough for the top leader of Hamas, Khaled Meshal. Speaking in Cairo on Monday, he taunted Israel to begin a ground invasion, saying “if you wanted to launch it, you would have done it.” He ignored the fact that an invasion would kill many more Palestinians and further devastate the Gaza Strip, which, in August, before the current fighting, the United Nations predicted would be unlivable by 2020.

Hamas, which took control of Gaza in 2007 and is backed by Iran, is so consumed with hatred for Israel that it has repeatedly resorted to violence, no matter the cost to its own people. Gaza militants have fired between 750 to 800 rockets into Israel this year before Israel assassinated one of its senior leaders last week and began its artillery and air campaigns. That approach will never get Palestinians the independent state most yearn for, but it is all Hamas has to offer.

Israel also has a responsibility for the current crisis, which threatens to complicate and divert attention from international attempts to deal with the threat of Iran’s nuclear program and the Syrian civil war. Israel has a right to defend itself, although it is doing so at the cost of further marginalizing the moderate Palestinian Authority that helps administer the West Bank and it risks further isolating Israel diplomatically.

Israel has a vastly more capable military than Hamas, and its air campaign has resulted in a lopsided casualty count: three Israelis have been killed. The Israelis claim to have done considerable damage to Hamas rocket targets, which should make a ground invasion of Gaza less likely. But military action is no long-term answer. If Prime Minister Benjamin Netanyahu of Israel had pursued serious negotiations on a two-state solution with the Palestinian president, Mahmoud Abbas, the Palestinians could have hope in a different future and Hamas’s nihilistic vision would have far less appeal. Mr. Abbas shares responsibility for this failure.