Donald Trump on Sunday came down firmly against intervening militarily in Syria to alleviate the humanitarian disaster there a direct contradiction of the remarks of his running mate, Indiana Gov. Mike Pence (R).

He and I havent spoken and I disagree, Trump responded, when ABC News Martha Raddatz asked him about the apparent discrepancy during Sunday nights presidential debate .

The comment showed a striking willingness on Trumps part to publicly break with his running mate. During last weeks vice presidential debate, Pence expressed support for creating humanitarian safe zones for civilians in Syria, which would almost certainly require a no-fly zone of some kind. He also suggested that the U.S. should be prepared to attack the government of Syrian President Bashar Assad to stop it from committing atrocities in the Syrian city of Aleppo.

If Trump and Pence have indeed not discussed the matter, its unclear why that would be. The Indiana governor said in August that he and Trump talk nearly every day .

Trump has voiced support for creating safe zones at least once in the past.

But for the most part, he has been skeptical of the United States intervening in Syria in any way that would undermine Assads hold on power , since he claims Assad is fighting the self-described Islamic State and other extremist groups.

Trump stuck to that approach on Sunday, questioning what would happen if the U.S. helped Syrian rebel groups oust Assad.

Democratic presidential nominee Hillary Clinton wants to fight for rebels, Trump said. Theres only one problem: You dont even know who the rebels are.

I dont like Assad at all, but Assad is killing ISIS, he added. Russia is killing ISIS.

In fact, as Clinton noted, there is ample evidence that the Syrian and Russian governments have focused their bombardments on non-extremist rebel groups and civilian targets .

Russia hasnt paid any attention to ISIS. They are interested in keeping Assad in power, she said.

Trump did not offer any new details about how he would aid civilians in Aleppo, which is experiencing a humanitarian crisis as the result of an intense Syrian and Russian bombing campaign there.

Clinton reiterated her support for establishing safe zones for Syrian civilians and a no-fly zone in parts of the country, which would require U.S. military to shoot down Syrian and Russian jets if they violate the airspace over those areas.

The former secretary of state believes this approach would confer an advantage to the U.S. when trying to engage Russia in talks to create a political resolution to the Syrian conflict.

Russia is not going to come to the negotiating table for a diplomatic resolution unless there is some leverage over them, Clinton said.

Clinton also said she would pursue war crime charges against figures in Assads government and in the Russian government.

Clinton did not rule out aerial bombardments of the Syrian government in other capacities as well, but said she would not send in U.S. ground troops.

I would not use American ground forces in Syria, Clinton said. I think that would be a very serious mistake. I do not think American troops should be holding territory, which is what they would have to do.

The U.S. military, however, has concluded that a no-fly zone would require ground troops, whether in Syria or in bordering nations. Gen. Martin Dempsey, at the time chairman of the Joint Chiefs of Staff, estimated in 2013, prior to Russian intervention in the country, that the U.S. would need thousands of ground forces for such an approach.

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