Add Kirstjen Nielsen to the ash heap of cabinet officials who broke themselves on the wheel of President Trump‘s runaway ego. The former Department of Homeland Security secretary “resigned” Sunday, sacrificed so Trump can save face on yet another con gone wrong.

Someone had to pay for Trump’s failure to close the southern border. Who better to blame than Nielsen, who routinely disappointed Trump by failing to carry out orders that violated federal and international statutes and the law of physics. Too lazy to learn anything, Trump couldn’t understand why Nielsen — who dutifully imprisoned immigrant children on his orders — couldn’t elevate his momentary whims above long-settled laws and time-honored norms of morality.

Nielsen could have kicked and screamed on her way out, but prudently chose to keep quiet. Criticizing Trump is no way to land an “analyst” job at Fox “News.” Nielsen knew to keep her mouth shut if she ever hoped to be heard from again.

Congressional Democrats have no excuse. Perennial slaves to style over substance, the party’s alleged leadership squandered yet another opportunity to call Trump’s bluff. When the president threatened to close the border, Pelosi, Schumer and other prominent Democrats should have replied: “Go ahead, Mr. President. Show us you’re not ‘playing games'”

This response would accomplish at least two objectives:.

  1. Trump would have to eat his empty threat.
  2. Trump would be exposed as a snake oil salesman hawking a product he can’t deliver.

Whether you agree that the border should be closed, it isn’t like putting a padlock on the backyard fence. It would be a long, costly process requiring massive military commitments and the violation of God knows how many federal laws and international commitments. These hurdles are high enough, but the one that rises above all others is profit.

Closing the border would erase an estimated $10 billion in economic activity every day. The impact would be “catastrophic,” according the famously liberal Sen. Mitch McConnell, who joined other Republicans like Texas Sen. Rafael “Ted” Cruz in telling Trump he can draw all the lines in the sand he likes — until he threatens to cross the bottom line.

Money talks. You know what walks, which is why Trump backpedaled over Kirstjen Nielsen. Someone had to take the fall for Trump’s flight of fascist fancy. She was a loyal soldier dispatched as cannon fodder by a bumbling general desperate to surrender without admitting defeat.

History will remember Kirstjen Nielsen, who sold her soul and got owned. Trump won’t give her a second thought.