Is the U.S.–Israel escalation pushing the Middle East toward all-out war?

The Middle East faces a historic turning point after Iran confirmed that its Supreme Leader, Ali Khamenei, was killed in U.S.–Israeli strikes. Tehran has formed an interim leadership council as it prepares to select the next Supreme Leader. U.S. President Donald Trump warned Iran against retaliation, saying American forces would respond with force "never seen before." Reactions worldwide are sharply divided. What strategic endgame are the United States and Israel pursuing in the region? And how far could the shockwaves spread?