'Tennessee not happy!' Trump attacks another GOP senator who questioned his fitness

President Donald Trump on Friday publicly attacked yet another Republican senator by name.

In a tweet posted on Friday morning, Trump slammed Sen. Bob Corker (R-TN) for questioning his fitness and competence to be president.

"Strange statement by Bob Corker considering that he is constantly asking me whether or not he should run again in '18," the president wrote. "Tennessee not happy!"

Last week, Corker said that Trump "has not yet been able to demonstrate the stability, nor some of the competence, that he needs to demonstrate in order to be successful," while also suggesting that the president " has not demonstrated that he understands the character of this nation."

Corker is the fifth Republican lawmaker that Trump has attacked publicly this week, along with Sen. Mitch McConnell (R-KY), Sen. Jeff Flake (R-AZ), Sen. John McCain (R-AZ), and Rep. Paul Ryan (R-WI).

Trump has made attacking members of his own party a staple of his governing strategy -- as CNN's Chris Cillizza notes, Trump has now publicly lashed out at 20 percent of currently serving Republican senators.