In the latest cycle of threats and concessions that have marked US President Donald Trump’s approach to the war that he and his Israeli counterpart started against Iran, the mercurial leader said on Thursday he would destroy any boat attempting to lay mines in the blocked Strait of Hormuz.

His focus on diminutive vessels followed his oft-repeated messaging that Iran’s larger naval vessels no longer exist as he renewed his effort to muscle Tehran’s frustratingly resilient regime to concede...