Sen. Bernie Sanders (I-Vt.) traditionally has operated by his own set of rules, seeking to promote his democratic socialist agenda often at the expense of the Democratic Party, under whose banner he was never elected to the Senate. He stayed in the 2016 race long after Hillary Clinton was the obvious winner and, if you listen to Clinton supporters, was less than all-in during the general election.

Over the past couple of weeks, despite Democratic voters’ pleas that the candidates not bloody each other, Sanders has gone negative, a striking departure from his past approach and from the approach of other candidates in the final stretch before the Iowa caucuses. He has taken to bashing former vice president Joe Biden about trade and the Iraq War and claiming (without evidence) that Biden is less electable than the 78-year-old socialist.

On Sunday, he got caught maligning Sen. Elizabeth Warren (D-Mass.), who has steadfastly refused to attack him, at least so far. The New York Times reports:

Ms. Warren said on Sunday she was “disappointed” that Mr. Sanders’s campaign had been using a script for volunteers that suggested she was appealing mainly to highly educated voters and would not be able to expand the Democratic Party coalition.
“I was disappointed to hear that Bernie is sending his volunteers out to trash me,” Ms. Warren said. “I hope Bernie reconsiders and turns his campaign in a different direction.”

Smartly sticking to the party unity theme, Warren argued in a not-very-subtle reminder of Sanders’s behavior in 2016, “We all saw the impact of the factionalism in 2016, and we can’t have a repeat of that. Democrats need to unite our party and that means pulling in all parts of the Democratic coalition."

Sanders denied responsibility for the script (is he not aware of what’s going on in his own campaign?), but that will not calm irate Warren supporters. (The Times quotes a Warren supporter in Iowa: "'Doesn’t surprise me about Bernie,' she said. ‘He went straight to the gutter with Hillary. More of the same.’”)

Part of Sanders’s script claims that unlike Sanders, Warren does not bring new people into the party. So far there is zero evidence to back this up. Moreover, one has to consider the moderate independents and winnable Republicans whom Sanders will lose in the general election — voters whom Biden or former mayor Pete Buttigieg or Sen. Amy Klobuchar (D-Minn.) could win over. In addition, the recent Post-Ipsos national poll shows that Sanders gets a smaller share (20 percent) of key African American voters than does Biden (48 percent). “Electability,” of course, will depend in large part on whether the Democratic nominee gets a big share of the African American vote. According to that survey, Biden would win 82 percent of African Americans in a general election, while Sanders would get only 74 percent.

Others in the Democratic Party, including former Bill Clinton spokesman Joe Lockhart, were not pleased with Sanders’s new attack-dog mentality:

Sanders campaign officials also attacked Biden on race, a seemingly futile exercise against the former vice president, whose African American base is solid. (The Sanders campaign’s antics on race also incurred the wrath of Democrats.)

Sanders’s emphasis on electability is ironic given his vulnerability on this very point. His Medicare-for-all plan (which he says is so expensive he does not need to explain how it is to be funded) and his far-left foreign policy views are easy targets for Trump. (President Barack Obama’s former campaign chief Jim Messina observed: “If I were a campaign manager for Donald Trump and I look at the field, I would very much want to run against Bernie Sanders. ... He can say, ‘I’m a business guy, the economy’s good and this guy’s a socialist.’”)

On foreign policy, The Post recounts that the ouster of dictator wannabe Evo Morales in Bolivia engendered bipartisan support but not from Sanders: “A sharply different response came from Sen. Bernie Sanders, who immediately condemned ‘what appears to be a coup.’ ”

Sanders’s foreign policy views often fall outside the mainstream position of Democratic officials and foreign policy gurus. He continues to praise the economic progress of China, a brutal regime that engages in cyberwarfare and is persecuting the Uighurs. (“'He’s not going to pretend we face remotely equivalent threats from left-wing authoritarianism than from right-wing authoritarianism,' said a senior Sanders aide, speaking on the condition of anonymity to be candid.” Apparently, China does not register high on Sanders’s list of international threats.)

Unlike Senate Democrats in the race, Sanders opposes NAFTA 2.0 despite its support from organized labor, which achieved labor enforcement provisions. Sanders’s views on Israel came under attack in 2016 when Hillary Clinton’s campaign and the Anti-Defamation League slapped him down for effectively accusing Israel of war crimes. (Sanders had claimed that Israel launched a disproportionate response in its war with Hamas and targeted Palestinian civilians.) His current position on yanking all troops from the Middle East leaves open the question as to whether he is content to see Russia and Iran dominate the region and to allow the Islamic State to regenerate.

In sum, Sanders would provide an easy target for Republicans and deprive the Democrats of a mainstream alternative to Trump who is steadier on foreign policy and fiscally more responsible. Sanders might have gone negative at just the wrong time — that is, on the eve of the Jan. 14 debate.

His opponents certainly will have every incentive to attack him, or at the very least defend themselves with some inconvenient truths about the socialist’s electability problems. Others such as Buttigieg and Klobuchar might choose to point out that negative attacks among septuagenarians is a good reason to find new, positive voices who can get things done. If nothing else, Sanders might wind up reminding Democrats that he really is not the candidate who’s best-equipped to unify the party.

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