Sen. Bernie Sanders (I-VT) has returned from his Unity Tour more committed than ever to restoring America's position as a protector of human rights.

"The problem is, we are not a parliamentary system of government," Sanders told AJ+'s Dena Takruri in defense of his caucusing with the Democrats. "That's not to say by any means that you can't have three parties… but I think right now where we are with the great danger of Donald Trump and the billionaire class and the reactionary agenda they are up against, I am right now trying again… to transform the Democratic Party in a very fundamental way."

Sanders' "Come Together and Fight Back" Tour with new Democratic Party Chair Tom Perez in April was heavily criticized by both progressives and moderates. On the other hand, the long-time independent was chosen as a messenger due to his own wariness of the party that many of his supporters feel "berned" him.

"Democrats have not put forward an agenda that speaks to the needs of people who are in pain," Sanders said—a statement he applies both nationally and internationally.

Regarding the effect of the Trump administration's "America First" plan on the Syrian refugee program, he asserted:

I think the entire world has failed its moral obligations [to refugees], but I think what the United States as the most powerful nation on earth has got to do is do our best to bring people together to try to hammer out what is enormously difficult.

"What I would do [as president] is demand that those countries, like Russia, which are supplying an incredible amount of arms and protection to Syria, stop doing it," Sanders added. "Assad is a war criminal, he is killing tens and hundreds of thousands of his own people, and we have got to put pressure on Russia and Iran to stop supporting this war criminal."

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