The debate that resonated inside the ornate Senate Foreign Relations Committee suite, where senators of a different era debated how to push back against Hitler in the 1930s and how to define Cold War strategy against the Soviet Union thereafter, featured Republicans who said they would vote for any bill that called for punishing Moscow or containing its power, even if they had differences over specific sanctions.

The trick for them is to bash Mr. Putin without impugning Mr. Trump.

“This was something everyone was for, until they weren’t,” Senator Angus King, independent of Maine, said this week. He mused on how the country came to this moment because of the president’s decision to trade an issue of huge geopolitical gravity — Ukraine’s security, and thus the United States’ — for a “domestic political errand,” as Mr. Trump’s own former top Russia adviser, Fiona Hill, put it so searingly in testimony last month.

But that is only the beginning of the contradictions in American foreign policy unearthed in the impeachment inquiry.

At Wednesday morning’s Senate hearing, Democrats and Republicans outdid one another in professing their devotion to standing up to Mr. Putin. Mr. Graham labeled Russia an “evil enemy” comparable to fighting “the Nazis and the Japanese” in World War II — a bit of exaggeration about the current level of conflict, perhaps, but symbolic of the mood on Capitol Hill.

“The president is not a Russian agent,” Senator Marco Rubio, Republican of Florida, declared, in the first and last mention of Mr. Trump during the hearing. Mr. Rubio went on to say that while he had doubts about some parts of the legislation, he would vote for it because he had to fight “information warfare.” He added that Republicans had to remember that “Vladimir Putin will do to us what he has done to everyone else.”