President Donald Trump is not one to shy away from insulting others. Journalists, politicians, celebrities -- Trump has made a habit of viciously insulting and criticizing anyone who dares stand in his way.
According to CNN, Donald Trump's habit of insulting those he perceives as adversaries is one of the most unpresidential things about the commander in chief.
At a campaign rally on Friday in Missouri, Trump may have managed to cross another red line. The president slammed late Senator John McCain, just weeks after his death, The Hill reports.
McCain's decision to vote against the Republican Party's push to overhaul former President Barack Obama's healthcare plan, Obamacare, is, for President Trump, good enough of a reason to criticize the late Senator.
Although Trump did not mention John McCain by name, it is clear that he was referring to the late Arizona senator in his anti-Obamacare speech.
"We had it defeated, unfortunately we lost a certain vote, but we lost all the Democrat votes when you think."
But, Trump and McCain's feud began much earlier, before the late senator even had the opportunity to cast his Obamacare vote.
As The Hill notes, Trump and McCain traded harsh rhetoric since Trump's time on the campaign trail. Trump infamously said that McCain was not a war hero because he was captured.
"He's not a war hero. He's a war hero because he was captured. I like people that weren't captured," then-candidate Trump said, according to NBC News.
Furthermore, according to the Business Insider, Trump reportedly told some of his closest allies that he does not regret his notorious "not a war hero" remarks about John McCain.
President Trump did, however, express his condolences following McCain's death, via Twitter.
"My deepest sympathies and respect go out to the family of Senator John McCain. Our hearts and prayers are with you," the president tweeted.
McCain's funeral -- which the late senator had been planning for weeks -- united all Americans, Republicans and Democrats, attracting widespread media attention. This is how John McCain "got the last word against Trump," as the New York Times put it.
If it is to judge by Trump's most recent comments about the late senator, he is not willing to let McCain have the last word.