Washington DC - Former presidential candidate Chris Christie recently criticized Donald Trump over his running mate pick, which he believes is countering his public calls for the country to unite.

On Tuesday, the former New Jersey governor published a scathing op-ed in The New York Times, where he argued that Trump "has the opportunity to rein in some of the worst rhetorical impulses of the Republican Party," yet is failing to do so.

Christie took aim at Trump's recent pick for his running mate, which he believes only appeals to the extreme end of the Republican Party.

"Mr. Trump's selection of Senator JD Vance of Ohio as his running mate doubles down on the portion of the party already completely devoted to him rather than reaches out to the broader party and beyond," Christie wrote.

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"Clearly, this is not a message of unity in the face of what could have been a national tragedy," he added.

Christie was referring to a recent shooting at Trump's rally in Butler, Pennsylvania, on July 13, where a gunman opened fire, wounding the former president and two others and killing one bystander.

Since the incident, Trump and others have called for "unity" across party lines, arguing that political discourse and rhetoric have reached vitriolic levels.

But Christie argued, "It is not enough for this to be only a momentary call for unity. This change has to go beyond this week, next month and the November elections to be a real transformational shift."

While Vance notably used to be a very outspoken critic of Trump, he has worked since 2021 to rebrand himself into a staunch MAGA Republican, publicly defending and supporting Trump at every turn and helping to push the former president's many lies, unfounded claims, harsh rhetoric, and conspiracy theories.

In spite of the calls for unity and civility, Vance and other MAGA Republicans have pushed the narrative that Trump's rival, President Joe Biden, and his Democrat allies are to blame for the shooting.

In a social media post shared only a few hours after the shooting, Vance argued that Biden had pushed the idea that Trump is "an authoritarian fascist who must be stopped at all costs," rhetoric he believes "led directly to" the assassination attempt.

In his op-ed, Christie slammed the "flawed" strategy, explaining, "Too many of the loudest voices in our national discourse are now incentivized to paint their opponents as not just wrong, but also out to destroy all we hold dear."