Perhaps the most conspicuous point of convergence for the two is on foreign policy. Operating at a remove from establishment Beltway circles, both Sanders and Trump have bucked the mainstream messaging of their parties. It's particularly apparent when it comes to discussing a resolution to the grim Syrian crisis.
Trump and Sanders repeatedly warn about the perils of regime change. They bring up the lessons of the 2003 invasion of Iraq and the toppling of dictator Saddam Hussein, an intervention that they (and many others) argue paved the way for the instability now wracking the Middle East.
That carries forward to the present moment, where both have expressed little opposition to the Russian entrance into the Syrian war and are lukewarm on the need to work against the regime of embattled Syrian leader Bashar al-Assad, who has presided over a conflict that has displaced half the Syrian population and sparked an enormous refugee crisis.
"Let's say you get rid of Assad, you knock out that government — who's gonna take over?" Trump asked, during an interview with CBS earlier this week. "The people that we're backing? And then you're gonna have, like, Libya?"
Trump was referring to the U.S.-backed NATO air war in 2011 against the government forces of dictator Moammar Gaddafi. The airstrikes enabled Libyan rebels to defeat and ultimately kill Gaddafi, yet the country has undergone a dangerous, deadly unraveling in the years since. Trump referred to the situation in Libya as a "mess."
He also praised Iraq's late leader as a secular bulwark against extremism.
"Had we not done anything — had our politicians gone to the beach and enjoyed the sun, we would be in a lot better position than we are right now," Trump said on CBS, referring to the decision to invade in 2003. "Saddam Hussein — no good guy but Saddam Hussein killed terrorists."
During Thursday's Democratic debate in Milwaukee, Sanders, who unlike Hillary Clinton, voted against the Iraq war, made a similar argument:
And God only knows Saddam Hussein was a brutal dictator. We could overthrow Assad tomorrow if we wanted to. We got rid of Gaddafi. But the point about foreign policy is not just to know that you can overthrow a terrible dictator, it's to understand what happens the day after.And in Libya, for example, the United States, Secretary Clinton, as secretary of state, working with some other countries, did get rid of a terrible dictator named Gaddafi. But what happened is a political vacuum developed. ISIS came in and now occupies significant territory in Libya and is now prepared, unless we stop them, to have a terrorist foothold.
In a December interview with NBC's "Meet the Press," Sanders argued that the Middle East "would be much more stable" were autocrats like Gaddafi and Hussein still in power.
In their platforms, both candidates, like all the others, harp on the need to defeat the Islamic State, the radical jihadist organization that continues to control territory in Iraq and Syria, while waging terror strikes all over the world through its proxies.
And so Trump has no problem with Moscow's air war in Syria.
"I love the fact that Russia is hitting ISIS," Trump told CBS, using a common acronym for the group. "And as far as I'm concerned, they've got to continue to hit ISIS."
But Russian airstrikes, while ostensibly aimed at combating the Islamic State, were actually focused on other rebel attacks and served to greatly strengthen the Assad regime's position.
That could explain Sanders's more cautious stance. He has not cheered Moscow's meddling and Thursday night denounced the "aggressive" actions of Russian President Vladimir Putin. But Sanders has also signaled the need for the United States to not involve itself in more costly imbroglios in the region.
"I am not a pacifist: I supported the war in Afghanistan, I supported President Clinton's effort to deal with ethnic cleansing in Kosovo, I support airstrikes in Syria," Sanders said at a Democratic presidential debate on CNN in October. "I happen to believe from the bottom of my heart that war should be the last resort."
This is where the Democratic candidate radically diverges from the Republican front-runner. Trump isn't interested in such moralizing: He promises tough relentless action against the jihadists and then suggests, improbably, that the United States should nab the region's oil profits.
Trump also has no time for the plight of Syrian refugees. He wants to halt all of their arrivals as well as those of any other Muslim in the United States, a bigoted talking point that won a disturbing amount of traction among the Republican base.
Sanders has a very different view on this and has stressed the need to welcome Syrian refugees and address the conflict's enormous humanitarian toll.
"It seems to me that given our history as a nation that has been a beacon of hope for the oppressed, for the downtrodden, that I very strongly disagree with those Republican candidates who say, you know what, we've got to turn our backs on women and children who left their home with nothing, nothing at all," Sanders said during the Thursday debate. "That is not what America is supposed to be about."
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