Weekly Standard editor-at-large Bill Kristol attacked Fox News host Tucker Carlson Tuesday night for an argument Kristol himself made in 2015.

Carlson, a Daily Caller co-founder, opened his Tuesday night show by saying the judgment of past historical figures by present standards is a dangerous proposition.

“The point is that if we’re going to judge the past by the standards of the present — if we’re going to reduce a person’s life to the single worst thing he ever participated in — we’d better be prepared for the consequences,” Carlson stated. “Here’s why: 41 of the 56 men who signed the Declaration of Independence were slave holders. James Madison, the father of the constitution, had a plantation full of slaves. George Mason, the father of the Bill of Rights, owned slaves. Does that make what they wrote illegitimate?”

After these remarks, Kristol decided it would be best to snark about his former employee on Twitter. “They started by rationalizing Trump. They ended by rationalizing slavery,” he wrote.

The conservative commentator then remarked in another tweet, “Next: Luther, Voltaire and Marx were anti-Jewish. So why’s it a big deal that the marchers were chanting, ‘Jews will not replace us?'”

While Kristol has reached the ripe age of 64, it’s surprising he forgot that he argued against rewriting history just two years ago in a podcast hosted by The Weekly Standard.

“I’ve noticed that some of the critics of the [Confederate flag] are now moving on to say that Lee Highway near me in Northern Virginia should be renamed,” Kristol said. “That I think is ridiculous. They were admirable people, individuals, who led the Confederacy.”

He continued on to say: “The idea that we are going to go on a jihad now against anyone that was associated with the Confederacy, or with the south, with segregation for that matter we could rename the Russell office building, which is one of the most prestigious of the Senate office buildings, named after a very impressive senator who was however a segregationist.”

The Weekly Standard editor said removing references to individuals associated with these racist acts would be “rewriting history and sort of expunging whole parts of your national tradition,” adding that Americans shouldn’t “be ashamed of admirable human beings who made bad decisions.”