President Donald Trump took on Sen. Jeff Flake, R-Ariz., in a Thursday morning tweet calling him "weak" and "toxic."
Flake has been a frequent critic of his own party, including President Trump. He wrote the book "Conscience of a Conservative," in which he said the GOP was in denial about Trump.
In an Aug. 7 interview with Newsmax TV, Flake said his party was compromised by "extreme nationalism."
"Real conservativeness is steadiness, and soberness, and predictability," Flake said in an interview on "Newsmax Now."