An A.I. video recently released by supporters of the Iranian government begins with a robed Shiite Muslim warrior approaching the White House on a stormy night, clutching an ornate split-bladed sword. In the next scene, the weapon slides across President Donald Trump’s cheek. Generated images depict present-day Iranian soldiers defending oil facilities under attack and capturing a U.S. aircraft carrier. Another group pays respects to the Grand Ayatollah Ali al-Sistani, the leading religious figure for millions of Shiites around the world, before launching what appears to be a suicide mission against enemies in Humvees. Then other soldiers attack oil tankers...