Ever-honest director and author Oliver Stone stopped by HuffPost Live on Tuesday to discuss Barack Obama's presidency, climate change and his new book and documentary series, "The Untold History of the United States."

Stone is an equal opportunity critic, arguing that neither Obama nor Mitt Romney tackled climate change in a substantive way. "I was a little disappointed at the third debate when neither of them talked about climate control and the nature of the situation on Earth," Stone said. "I think there's kind of a weird statement coming right after ... this is a punishment ... Mother Nature cannot be ignored. That's all I thought about."

American exceptionalism is among Stone's "There's this attitude that we 'deserve' to be in charge," Stone said. "I don't believe in that ... We act as if we have this right of kingship -- we act as tyrants."

"We learn the history of the victors," Peter Kuznick, a history professor at American University and partner of Oliver Stone said. "We learn this triumphant version of history, that the United States is the shining city on the hill."

Despite his criticisms of the Obama administration, Stone freely admitted that he had already pre-voted in support of the president's reelection. The filmmaker's main reasons for casting his ballot in Obama's favor were based on the president's ability to think rationally and perform "brilliantly" in the context of debates.

Though both Stone and Kuznick predicted that Obama would win, Stone humored HuffPost Live host Alyona Minkovski with a guess at what a Romney presidency would look like. "It certainly means more militarism ... there's no talk of cutting back," Stone forecasted.

Stone, an ardent advocate of marijuana legalization, argued that "there is nothing harmful in marijuana" and had a clear message for anti-pot politicians: "Stop this nonsense."

When asked if the project's political tenor made it difficult to finance and produce, Stone said that while "The Untold History of the United States" is "love work," the series and book are "the most cumbersome project I've ever been involved with."

Getting the ten-hour series on television was a sizable task, Stone said, arguing that while PBS or other public stations may have once shown such a program, "they're so politicized they can't say anything -- they're scared of their own shadow." Instead, Stone argues PBS has settled for making "this Pro-American experience type stuff, where it has to be about America and America has to be the point of making the movie."

President George W. Bush also made it into the segment, albeit only as a playful aside. "I was in Bush's class [at Yale], so that tells you a bit about what we were taught at the time," Stone quipped.

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