Captain Planet and the Planeteers (1990)

S6E5 A Good Bomb Is Hard to Find

Dr. Blight uses her newest time travel technology to come back from two decades ahead, delivering a shocking message to her past self: the world is now a place of peace! Determined to reignite the Cold War, both versions of Blight join forces to steal a stash of plutonium from decommissioned warheads. They then make their way back to earlier times, aiming to sell nuclear weapons to the highest bidder and restore chaos to the world.