Longtime liberal activist Ralph Nader is often blamed for costing Al Gore the 2000 election, but that hasn't swayed him from attacking President Obama and calling him a "war criminal" (video below).

Nader told Politico.com that President Obama is worse than President george W. Bush, who invaded two countries during his term.

Nader said: "He's gone beyond George W. Bush in drones, for example. He thinks the world is his plate, that national sovereignties mean nothing, drones can go anywhere. They can kill anybody that he suspects and every Tuesday he makes the call on who lives and who dies, supposed suspects in places like Yemen and Pakistan and Afghanistan, and that is a war crime and he ought to be held to account."

Nader added that President Obama has "has legitimized the lawless war-mongering and militarism abroad of George W. Bush."

Additionally, Nader called the current GOP the "the worst Republican Party in history."

Nader said: "We're dealing with a real sick, decaying Democratic Party that can't defend the country against the cruelest, most ignorant, most anti-worker, most war-mongering, most Wall Street - indentured Republican Party in its history, since the 1850s."