CBS blinked first.

After less than three hours of live coverage on Tuesday, the network of Walter Cronkite cut away from the Senate impeachment trial of President Trump, yielding to daytime fare like “Dr. Phil” and “Judge Judy.”

NBC held out longer, but by 5 p.m., ABC was the last traditional broadcast network still in breaking-news mode. Die-hards could turn to cable news for their fix.

In television terms, the opening hours of Mr. Trump’s trial — only the third in American history, and the second of the mass-media era — did not exactly make for visually compelling viewing. For Republican Senate leadership, that was by design.

Senate officials rejected repeated requests to allow outside cameras into the chamber to record the trial — meaning that what viewers see and hear will be dictated by cameras and microphones controlled by Senate staff members, rather than an independent news organization. (Even C-SPAN was not allowed access.)