The seizure of the tanker "Skipper" by USA forces off Venezuela highlights a wider crackdown on a roughly 1,000-vessel dark fleet that moves sanctioned oil for Iran, Venezuela, Russia, and Cuba. Maritime analysts describe how these aging, uninsured tankers spoof navigation signals, falsify flags, and use fraudulent registrations, creating serious environmental and crew-safety risks while funding autocratic regimes and the war in Ukraine. Officials in the USA and Ukraine frame ship seizures, legal boardings under international law, and Ukrainian sea-drone strikes in the Black Sea as a coordinated strategy to counter gray-zone aggression and disrupt illicit oil revenues.