Former Sen. Chuck Hagel (R-NE) faces his long-anticipated confirmation hearing today before the Senate Armed Services Committee for the position of Secretary of Defense. The hearing will not only be an examination of Hagel’s qualifications and views, but will test whether the Senate’s “advice and consent” process is a serious filter for potential Cabinet nominees, or merely a rubber stamp and a forum for political grandstanding.

The Senate’s recent performances have not inspired much confidence. Outgoing Secretary of State Hillary Clinton put on a dramatic yet thoroughly evasive performance during a hearing on the Benghazi attack last week. Her successor, John Kerry, faced few tough questions about his questionable record on foreign policy issues. Senators used the allotted time to offer their own views but wasted an opportunity to question his.

Democrats in particular have shown little inclination to question any of the president’s nominees, and made a show of their uniformly effusive praise for Clinton. The partisan divide created around President Obama is evidently so polarizing that Democrats are more concerned about falling in line than they are about defending the legislative body to which they were elected, which has traditionally shown far more independence.

Had a Republican president–or perhaps any other Democratic president–nominated a Republican for such an important post with such thin qualifications, such controversial views and such a troubled history of prejudicial statements, Democrats would have been lining up to lead the opposition effort. Sen. Chuck Schumer of New York, who styles himself as Israel’s “guardian” on Capitol Hill, would have been among the first.

Hagel ought to be asked about his lack of specific qualifications for the job, other than his military service. He ought to be asked about his many “confirmation conversions”–on a nuclear Iran, on nuclear disarmament, on the U.S. alliance with Israel, on abortion, on gay issues, and on the “Jewish lobby,” to name a few. And he ought to be asked to explain his bizarre associations with radical groups such as J Street and Global Zero.

The Senate might also consider asking Pentagon officials to testify about why they have spent weeks lobbying Senators to confirm Hagel, even though he does not even work there yet. On the surface, the Pentagon’s campaign seems to be a clear violation of the separation of powers and a troubling sign of the politicization of the Department of Defense. Which officials were involved, and on whose orders? The Senate should ask.

It is understandable, though not admirable, that some organizations that are strenuously opposed to Hagel’s positions have done nothing to resist his confirmation. The vaunted American Israel Public Affairs Committee (AIPAC) has remained silent on the sidelines, afraid to risk its political capital and lose, leaving the fight to Christians United for Israel (CUFI) and the Republican Jewish Coalition (RJC), which have led public opposition.  

Yet the Senate has a duty to fulfill. It cannot simply let nominees through based on the facile notion that “elections have consequences.” The Constitution was designed to limit those consequences, and gave the Senate not just the function of “Consent” but the role of “Advice.” Hagel’s confirmation hearing will be a true test of whether Senators–and Democrats in particular–have any intention of honoring their constitutional obligation.