Many bashed the retiring senator for letting Trump have his way far too often.
“It’s juvenile. The whole thing is juvenile,” the retiring Senate Foreign Relations Committee chairman said of Trump's push for a wall.
"That's tyranny, isn't it?" the senator said, according to CNN.
The Tennessee Republican ripped the latest threat as yet another "precipitous" decision by the president.
The GOP senator believes republicanism under the president is an "anomaly."
"There's not a smoking gun. There's a smoking saw," Lindsey Graham said.
They want to know whether Crown Prince Mohammed bin Salman was personally responsible.
Sen. Bob Corker (R-Tenn.) said he believes Saudi Crown Prince Mohammed bin Salman was involved in the journalist's killing.
Lawmakers can take key steps immediately, and vital votes are on the horizon.
Ahead of the rally, President Donald Trump said he thought the Saudi explanation for Jamal Khashoggi's death was "credible."