U.S. Sen. John Kennedy's getting a lot of ink these days for his plain-spoken, often amusing quips. Perhaps he deserves even more for being an increasingly reliable barometer how controversies are playing in public.

Kennedy, it should be said, is no enemy of the Trump administration. While he's had some mavericky moments since moving to Washington last year, he is a reliable Republican vote. And unlike many, many others who routinely find fault with President Donald Trump, he's happy to defend the president's intentions.

But when he has broken free from the party line, he's usually done so when the official position has become, frankly, ridiculous.



More than just about any other Trump loyalist, Kennedy has picked his targets well. He's gone after painfully unqualified judicial nominees. He's criticized Congress for holding up renewal of the popular Children's Health Insurance Program. He's questioned White House chief of staff John Kelly's ham-fisted (at best) handling of news that top aide Rob Porter had been accused by two ex-wives of domestic abuse.

Kennedy was an early critic of former Health and Human Services Secretary Tom Price for taking expensive charter flights, not long before he was forced from the job. And this week, Kennedy turned on EPA administrator Scott Pruitt amid news reports that he routinely flies first-class on the taxpayer dime for vague security reasons — or, more plausibly, to avoid the unpleasantness in coach.

“I would be embarrassed to get on a plane, sit down in first class and have my constituents pass me by and see me in first class," Kennedy told Politico. "I just think all Cabinet secretaries and all of us ought to fly coach.”

During his long tenure as Louisiana state treasurer, Kennedy showed a keen sense of how political news was playing in public, and that hasn't changed now that he's a senator.

So here's a good rule of thumb for the administration and Republican leaders in Congress: If you've lost John Kennedy, you've probably lost the argument.

Follow Stephanie Grace on Twitter, @stephgracela.