Republicans are so far signaling that they won’t filibuster Mr. Hagel, which speaks well of their confirmation consistency even with a Democrat in the White House. But Senators of either party still owe voters their independent judgment on an up or down vote. Advice and consent isn’t supposed to mean partisan deference to the White House, especially when a nominee looks as unprepared as Mr. Hagel does.

It’s clear that Mr. Obama chose Mr. Hagel not because he wants a strong and knowledgeable adviser but because he wants a cipher who will take orders from the White House. Mr. Hagel all but admitted this at last month’s hearing when West Virginia Democrat Joe Manchin noted that “you’re going to be basically following policy, not making policy.” Mr. Hagel replied, “I won’t be in a policy-making position.”

So at a time of global turmoil and growing White House pressure to gut defense, the Pentagon gets a potted plant. Imagine Don Rumsfeld or Henry Kissinger declaring that they took a policy job in which they could not make policy. Mr. Hagel is unlikely to be an effective public spokesman and he lacks the knowledge to wrestle intelligently with the Pentagon’s many competing interests.