The death of Hezbollah leader Hassan Nasrallah in an Israeli airstrike has weakened Iran's key deterrent against Israel. Iran's response to this loss will have significant implications for the region and beyond. With Hezbollah decimated, Iran may have no choice but to take action, which could escalate the conflict. Experts suggest that Iran's options range from unpalatable to ugly, and the decisions it makes will shape the next stage of the growing conflict. The risk of a dangerous conflagration in the Middle East has significantly increased, and there are concerns that Iran may pursue nuclear weapons as a form of deterrence.