President Trump started off the New Year by adding retired Gen. Stanley McChrystal to the list of perceived enemies he has insulted as “a dog” over the years.

“’General’ McChrystal got fired like a dog by Obama. Last assignment a total bust. Known for big, dumb mouth. Hillary lover!” the commander-in-chief exclaimed on Twitter at 10:32 a.m.

The president also retweeted an article from conservative talking head Laura Ingraham’s website Lifezette titled “Media Didn’t Like McChrystal Until He Started Bashing Trump.”

The highly decorated former top commander in Afghanistan — a West Point grad who also served in both Iraq wars — said Sunday that Trump’s sudden decision to withdraw up to half the 14,000 American troops serving there would reduce any incentive for the Taliban to negotiate a peace deal after more than 17 years of war.

McChrystal had said the US had “basically traded away the biggest leverage point we have.”

He also slammed Trump personally, saying he didn’t believe the president was honest.

The comment came when he was asked what he would say if he were asked to join the Trump administration.

“I think it’s important for me to work for people who I think are basically honest, who tell the truth as best they know it,” he said.

When asked if Trump was immoral, McChrystal responded: “I think he is.”

It’s not the first time he’s criticized a sitting president.

President Barack Obama accepted McChrystal’s resignation in June 2010 after he made scathing remarks in a magazine article about administration officials, including Obama and Vice President Joe Biden.

Labeling someone “a dog” or saying they were “fired like a dog” is one of Trump’s recurring Twitter themes.

In recent years, the president — who, according to multiple accounts, doesn’t care much for man’s best friend — has referred to former aide Omarosa Manigault, GOP Sen. Ted Cruz, ex-top strategist Steve Bannon, conservative talker Glen Beck, NBC reporters David Gregory and Chuck Todd, comedian Bill Maher and pundit Ariana Huffington, among others, as dogs.