After Donald Trump attacked Arizona Senator John McCain during an interview on an Alabama conservative radio station, his supporters were quick to cheer on the president. In response, one host on MSNBC wasted no time sounding off.

"Morning Joe" on Trump

It's no secret that Donald Trump and John McCain don't see to eye. The feud between the two dates back to the early days of the 2016 presidential election when the former host of "The Apprentice" came under fire for claiming McCain wasn't a war hero because he was captured during the Vietnam War and made into a POW.

"He's not a war hero," Trump said, before later explaining, "I like people who weren't captured." Trump ripped into the senator several times during the election due to McCain's lack of support, which has continued in the nine months that he's been president. The latest rift comes in the form of McCain announcing he will vote "No" on the GOP bill to repeal and replace Obamacare, which was co-sponsored by fellow Republican senators Lindsey Graham and Bill Cassidy. In response to the news, Trump went on a conservative radio station in Alabama on Monday and trashed the senator before taking to Twitter with an additional attack, leading to the issue being front and center on the September 26 edition of "Morning Joe" on MSNBC.

During the Tuesday morning edition of "Morning Joe," co-host Joe Scarborough made sure to hit back against Donald Trump for calling out John McCain, who recently announced he is suffering from brain cancer, while ripping into the president's supporters. "You have a man who is dying and you are using him for political punch lines on talk radio, and also audiences in Alabama?" Scarborough wondered.

Joe Scarborough went on to tell those who continue to support Donald Trump and bash John McCain to "keep your mouth shut." "Show a little respect, show a little dignitary, show a little class," the MSNBC host added. "Who raised these people?" Scarborough rhetorically asked, before adding, "Who have they become that they would boo a man who is fighting for his very life." Scarborough then pointed out McCain's military history, bringing up his time as POW in Vietnam where he refused to be released until the rest of his men joined him.

Trump vs Joe

This isn't the first time that "Morning Joe" has called out Donald Trump, as the hosts on the program have become one of the leading voices in opposition to the commander in chief. Once friendly with the billionaire real estate mogul, that relationship has turned sour, peaking when the president went on a fiery Twitter rant earlier this year against Scarborough and co-host, and fiance, Mika Brzezinski.

Next up

As John McCain fights in his battle against cancer, Donald Trump doesn't seem to let that impact his decision to attack the veteran senator from Arizona. Despite the support that the president has gotten from is core base on almost every issue, the majority of the American people are not standing by his side, with Trump sitting on an approval rating that has dropped to just 35 percent in the one of the most recently released polls on the issue.