India, July 8 -- The US military launched a fresh wave of strikes against Iranian targets early Wednesday, hours after three merchant ships came under attack in the Strait of Hormuz, dealing a serious blow to a month-old ceasefire arrangement and casting new doubt over the prospects of a lasting peace between Washington and Tehran.

US Central Command said in a statement posted to social media that American forces struck Iranian targets "to impose heavy costs for targeting and attacking commercial shipping crewed by innocent civilians in an international waterway." The command characterised Iran's conduct in blunt terms, saying its "demonstrated aggression was unwarranted, dangerous, and a clear violation of the ceasefire."

The retaliati...