IRAN and the United States each fired barrages of missiles today, as the pattern of tit-for-tat strikes took hold again and hope dimmed for any quick resolution. After a brief respite, the risk of a return to all-out war emerged once more, with the fighting threatening to engulf even more countries. The Iranian attacks came after the US military said it completed “a heavy wave of strikes against Iran,” conducted in response to an earlier Iranian missile attack on a US base in Jordan. President Donald Trump vowed to hit Iran “very hard” after it targeted the base. Before the latest eruption, mediators had expressed optimism about bringing Iran and the US back to the negotiating table.