Closing the waterway could choke the global economy and Iran has mines, fast attack vessels, submarines, drones and missiles it could use to stop ships coming through.
The strikes on Iran on Saturday led to the death of Iran's Supreme Leader, Ali Khamenei. Tehran has retaliated and, with rocket fire ongoing, disruption is set to continue.
What the killing of supreme leader Ali Khamenei and other Iranian top brass means for Iran's regime remains to be seen. But three global implications are already evident.
Khamenei's decades in power were characterised by a cult of personality, and his decrees were absolute. Under his rule, Iran's economy meandered and declined under punitive sanctions that hobbled his nation and led to unrest.