The war could have far-reaching implications for the regional order. Iran has reasserted itself as a counterbalance to Israel in an otherwise unipolar West Asia. Tehran is likely to rebuild its conventional arsenal, bolster relationships with Russia and China and reset ties in the region. On the other side, Israel’s over-reliance on the U.S. was again laid bare when faced with major conventional challenges. When it launched the war, it knew that it would not be able to destroy Iran’s nuclear facilities on its own. The U.S., which was participating in the defence of Israel by intercepting Iranian projectiles, joined in, giving Tel Aviv an exit strategy. But the U.S., which has burnt its fingers in Afghanistan, Iraq and Libya, did not want to get entangled in another forever war. This left Mr. Netanyahu with no other option but to accept a ceasefire with the regime he wanted to overthrow. U.S. intelligence agencies assess that the Iranian nuclear programme has been set back by only a few months. In effect, the war failed to deliver its objective and has brought the situation full circle: the urgent need for a diplomatic solution. For diplomacy to succeed, the U.S. must engage in serious talks with credible promises of economic benefits for Iran in return for accepting long-term, verifiable limits on its nuclear programme. Second, Washington must rein in Israel. As long as its closest ally continues to bomb its enemies with impunity, order and stability will remain out of reach for West Asia.