Iran’s Grip on Hormuz Is Tighter Than Ever After a Month of War

Israel and US strikes have wiped out senior Iranian leaders and hit key targets across the country. But after a month of fighting, it is arguably Iran that has secured the most significant strategic victory — a tightening grip over traffic through the Strait of Hormuz.

So far in March, the first full month of war, barely six vessels per day on average have traversed the narrow waterway connecting the Persian Gulf to the world, in either direction. That compares with about 135 a day in normal times, according to ship-tracking data compiled by Bloomberg.

Over that time, 80% of ...