MSNBC hosts Joe Scarborough and Mika Brzezinski agree: Democrats in Congress should boycott Israeli Prime Minister Benjamin Netanyahu when he appears before a joint session of the federal legislature next month. The reasons why they agree, however, diverge greatly.

During a Monday morning segment in which the hosts discussed the controversy that has erupted in the wake of the GOP’s decision to invite the Israeli prime minister to address Congress while the administration is struggling to strike a deal with Iran that will stall their development of nuclear weapons, tensions boiled over.

What set Scarborough off in this segment was not merely Brzezinski’s body language, which clearly communicated her distaste with what she appears to regard as moral posturing by her on-camera comrades, but her apparent determination that Republicans – including her co-hosts – were being dishonest. Their concerns were not for a rapidly nuclearizing state supporter of terrorism or the embattled Israeli people, and it certainly wasn’t for Jews around the world contending with increasing anti-Semitic violence, Brzezinski apparently reasoned. Their only interest was in embarrassing President Barack Obama. This determination led her to offer a mock compliment to her fellows when she observed, “You guys are good at what you do.”

This bit of projection from Brzezinski clearly frustrated Scarborough:

“I wouldn’t be quite so smug about mocking somebody as Jews are being gunned down in the streets of Paris and being attacked across Europe,” he insisted. “Go ahead, be smug about it. You don’t understand what Jews are going through.”

“The more this president shows his hand on what he thinks about Middle East politics, and the more chaos that we have in the world, the more I think, yes, it was,” Scarborough said when asked if it was a “good call” for Republicans to invite Netanyahu to speak. “That Benjamin Netanyahu, the people of Israel, and Jews across the globe need to know that there is at least one country, one country, that understands what they’re going through.”

“Let me say to Democrats out there, I would love you, politically as a Republican, to boycott this,” he said. “Please. Boycott it. Please, stay away.” Brzezinski apparently agreed.

Though she likely has the best interests of her party at heart, Brzezinski is falling into a trap into which so many of her fellow Democrats find themselves. Far too many on the left have conflated their party’s long-term interests with the near-term concerns of the president.

As I’ve written in prior posts on this subject, Netanyahu is generally well-liked among Americans when compared with other foreign leaders. The subject of Israel, too, does not rouse most Americans to gnash their teeth. As for a “boycott” of Netanyahu’s speech, only a handful of congressional Democrats are committed to shunning the Israeli prime minister in solidarity with the White House. Those Democrats hail from only the most partisan districts in which Democrats are wildly overrepresented. Those liberal legislators will be skipping Netanyahu’s speech not because they are ideologically predisposed to disagree with Israel’s objections to a proposed nuclear accord with Iran, but because they feel they must demonstrate their loyalty to Barack Obama through their actions.

That is the lamentable place in which the Democratic Party finds itself. It is no longer a party of ideas, but a reactionary force dedicated to defending the accomplishments of an earlier generation of progressives against the withering and constant assaults of modernity. It has also become a party of personalities.

How else does one explain this protest against Netanyahu? The left is not professing their fealty to a set of policy goals that a majority on the left believe are best for the nation and the world so much as they are defending the president’s honor against imagined slights committed by the opposition party in Congress. For Democrats like Brzezinski, their opposition to Netanyahu is personal.

When Obama leaves office, the ideological mooring that once guided Democrats will cast off with him. The party that was once united by a progressive vision will be set adrift. Then, all the smug posturing in the world won’t be able to substitute for a guiding set of principles, and sneering condescension that has become the left’s primary rhetorical weapon will prove an unconvincing substitute for a governing doctrine.