WASHINGTON — Republican Sen. John McCain left no doubt Monday that he was thinking of President Trump as he criticized the draft system during Vietnam for forcing low-income Americans to serve while the wealthy could avoid war with a doctor’s note.

McCain, a former Navy pilot and prisoner of war, stopped short of labeling Trump a “draft dodger” for getting five draft deferments. But the senator’s comments came with Trump already immersed in controversy over how he honors U.S. troop deaths, and underscored the remove between the billionaire president and the military system he now controls as commander in chief.

McCain’s criticism also continued a long-running clash between the two men on the eve of a visit by Trump to Capitol Hill on Tuesday to court Senate Republican votes for his tax plan, a meeting that could contain more than a few awkward moments.

“I don’t consider him so much a draft dodger as I feel that the system was so wrong that certain Americans could evade their responsibilities to serve the country,” McCain said on ABC’s “The View.” He was being pressed about comments in a C-SPAN interview aired Sunday where he lamented that the military “drafted the lowest income level of America and the highest income level found a doctor that would say they had a bone spur.”

One of Trump’s deferments came as a result of a physician’s letter stating he suffered from bone spurs in his feet.

McCain, meanwhile, spent 51/2 years as a prisoner of war after his plane was shot down over North Vietnam in 1967. Yet during last year’s presidential campaign Trump said McCain was not a war hero because “I like people who weren’t captured.”

The senator made clear during Monday’s interview that he had been referring to Trump in his C-SPAN comments. When asked to describe his relationship with the president. He said, “Almost none.”