Over the course of four years, Mike Pence served as former President Trump's vice president. In 2020, Pence happily campaigned alongside Trump in the hopes they'd win re-election.

Four years later, the former president is seeking another term in the Oval Office. Although this time, the ex-vice president isn't joining him at rallies, hosting events on his behalf, or otherwise stumping for the Trump 2024 campaign.

In fact, Pence has even made it clear that he's not supportive of Trump getting back into the White House. This weekend, the former vice president reiterated he won't be endorsing his previous running mate.

Why isn't Pence endorsing Trump this time around?

Pence previously went on the record, stating Trump pressured him to put politics over the US Constitution on January 6, 2021. Per the vice president, he declined to do this and doesn't believe anyone who puts themselves before the nation's Constitution should be in the White House.

Nevertheless, Pence also made it clear that his decision not to support Trump goes far beyond January 6. The former vice president cited Trump's walkback from supporting a TikTok ban and descriptions of people hit with criminal charges in the aftermath of January 6 as "hostages" as reasons why he won't be giving an endorsement.

Regarding the latter point, Pence said it was "unfortunate" for the ex-president to deem the aforementioned individuals as "hostages" when some American citizens remain held captive in Gaza.

Trump's supporters aren't happy about this

On social media, Republicans who endorsed Trump made clear their dismay with Pence's refusal to follow suit. South Dakota Gov. Kristi Noem, for instance, shared a video of the former vice president announcing his decision not to endorse with a caption questioning what Pence was doing.

Judging from their reactions, it's clear that much of Trump's base assumed that Pence's support for his former running mate would be a given. Though the events that happened on January 6, coupled with various policy disputes, have led the former vice president to distance himself from Trump.

So far, Pence has not definitively stated whether he'll vote for the former president over Biden in the general election.