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In response to the barbed discourse that can come from President Trump himself, the responses of his enemies have ramped up over the years, intensified by a crowd of Democrats who seek to oust him. What began as simple recoil against his policies has morphed into personal attacks that have sought to paint him as a racist, a homophobe, an Islamophobe, a xenophobe, a misogynist, a serial sexual predator and a Russian spy. It is hard to imagine a tactic that would even raise eyebrows after years of such onslaughts.

That’s why one of the lowest, most repulsive acts by any Trump opponent occupies such a singular place in the annals of dirty tricks: it is not first and foremost an attack on Trump; it is an act of malice toward regular citizens for the crime of writing checks to the Trump campaign.

At this still-early juncture in the 2020 Democratic nomination race, one name that has jumped from obscurity to respectful consideration is Julian Castro, HUD Secretary under Barack Obama and former mayor of San Antonio, where his twin brother Joaquin is a member of Congress and Julian’s campaign manager.

The Julian Castro campaign has enjoyed some traction of late as a result of praiseworthy debate performances and a resulting increase in TV attention. It cannot therefore be a good development when his brother manages to draw sharp rebukes from all sides with an act of stunning callousness and stupidity.

The Democrats in the field are running against each other while also projecting ahead to a run against Trump. That means their days are filled with strategies to outdistance current rivals as well as stances designed to convince Democrat voters that they are worthy warriors against the shared enemy.

It is hard to imagine the thought process that led Joaquin to ponder a single tweet that has ripped every ounce of positive attention from his brother’s campaign in what will now be a wave of revulsion directed toward him.

“Sad to see so many San Antonians as 2019 maximum donors to Donald Trump,” it begins. “Sad?” It is actually dispiriting to discover that Republicans actually exist in your city? But this oddity pales as the attack thickens.

He mentions two restaurant owners and a realtor by name and Twitter handle, then unfolds a list of 44 citizens who have committed the unpardonable sin of holding beliefs that differ from his.

This act of doxxing, now common among the unhinged left, does not contain the full home addresses and cell numbers that can often be part of the offense. But a teen with a smartphone could appear at many of the victims’ homes or businesses within minutes. Donor names alongside the names of their businesses constitute a hit list of San Antonians laid bare to whatever fate might await them from hopped-up, mischievous aggressors.

Not every name was joined to a business. Some said simply, “Homemaker.” “Self-employed.” “Retired.” In these amped-up times, imagine the shock of seeing your name blasted across America in an act of political savagery. But Joaquin was not done. The vote-shaming was not enough.

“Their contributions are fueling a campaign of hate that labels Hispanic immigrants as ‘invaders,’” he added-- a cherry on top that completes this despicable act with an unwarranted charge of complicity in a supremacist exercise, an accusation wrapped in a lie. One can like or dislike the “invaders” metaphor, but Trump reserves it for immigrants who break American law.

Attacks on the president are one thing. That daily drumbeat is now background noise. When the left began broadly attacking millions of Trump voters, that tone took on a special air of hostility. But this is singularly treacherous. This is a house-by-house, business-by-business, name-by-name political smear of Joaquin Castro’s own neighbors.

It remains on Twitter as of this writing despite what appears to be a clear violation of the platform’s terms of service. Rep. Castro spent a pathetic day online and in TV interviews insisting he had done nothing wrong. “There was no call to action,” he stated, as if one was needed. Have people needed a call tom action to torment Republicans in restaurants? Have they needed a call to action to terrorize them at their homes? No rallying cry is necessary when such outrageous acts come naturally to a corner of the Democratic Party Joaquin Castro is surely aware of.

And he did not care.

I could not care less what happens to his Twitter account. I am rather enjoying watching his lame attempts to defend the indefensible, most often with the assertion that the names are public record.

Indeed they are, and if I wanted to find them I could. If I wanted to defame them online, I could do that too, but it would approach a terroristic threat. Anyone thinking that language is overstated should visit Steve Scalise.

Rep. Castro removed the need for detective work as he curated and plastered those 44 names on his Twitter feed accompanied by a shameless attack on their character. And to the Congressman and his protectors dismissing the gravity of this stunt, let’s have some actual neo-Nazis post a list of prominent Jews. Perhaps that would illustrate the raw wickedness of what he has done.

A congressional censure motion is appropriate, even though it would go precisely nowhere in a Democratic-led house. But it would give Republicans (and any courageous Democrats) a chance to speak out against the kind of bottom-feeding that has millions of Americans disgusted with the entire political scene. And those opposing censure would feel the harsh glare of attention as they side with an act of unparalleled disregard for the well-being and reputation of Joaquin Castro’s victims.