A man walks across the seal of the Central Intelligence Agency at the lobby of the Original Headquarters Building at the CIA headquarters February 19, 2009 in McLean, Virginia. (Alex Wong/Getty Images)

The Senate Select Committee on Intelligence’s sickening report about the torture of terrorism suspects by CIA officers and contractors, with its revelations about “rectal feeding” and prolonged sleep deprivation, should trouble the conscience of every American.

Yet what’s potentially most dangerous to this country’s democratic future is not so much that these abuses occurred, which was already well established, but that congressional oversight of the CIA, and public discussion of it, should be developing along the same partisan political lines that quickly form around every other issue in today’s polarized Washington.

The report documents CIA actions during the administration of a Republican president, George W. Bush. Democratic senators’ staffers produced it; Republican input consisted of sitting out the investigation, then issuing a lengthy rebuttal that one-sidedly exonerated the Bush-era CIA.

Only one Republican senator, Arizona’s John McCain, unequivocally defended the report. Just one prominent Democrat denounced it: In USA Today, former Nebraska senator Bob Kerrey wrote that the Democratic staff “started out with the premise that the CIA was guilty and then worked to prove it.”

Thus does the United States approach a slippery slope, at the bottom of which lies an intelligence community that sees itself as the whipping boy of one political party and protected favorite of another — to the latter of which it owes reciprocal obligations.

If that ever comes to pass — if James Madison’s “spirit of faction” ever takes root within the government’s least transparent agencies — American democracy might suffer irreparable harm.

To be sure, some would say that the CIA, National Security Agency and the rest have long since slipped out of political or judicial control. Also, your average intelligence officer — or military officer, for that matter — has probably always been a tad on the conservative side. That’s who the job attracts.

But personal ideology, or even voting preference, is not the same as party loyalty. And for all the sins of the large, intrusive, difficult-to-manage U.S. intelligence apparatus over the years, it has generally remained free of outright political partisanship.

This is a crucial, if underappreciated, reason that it’s so hyperbolic to speak of a “United Stasi of America” — claims by Edward Snowden and his supporters to the contrary notwithstanding.

What made the Stasi, Gestapo and KGB especially threatening to political freedom was their subordination to, and seamless integration with, totalitarian political parties. Those parties’ ambitions were especially monstrous, to be sure. But for a secret intelligence service, even ideologically moderate partisanship would be corrosive and corrupting, both for itself and for the wider society.

From its inception under President Harry Truman, the United States’ post-World War II intelligence community has been a bipartisan — and, therefore, nonpartisan — institution, born as it was from a sense that Americans, whether Republican or Democratic, had common interests that needed protection from common external threats.

That ideal, of course, did not necessarily describe the agencies that conducted domestic surveillance and other abuses during the ’60s and ’70s. What’s noteworthy in retrospect about that era, though, is that the political system still mustered enough consensus to impose reforms, including regular oversight of the CIA by the very Senate intelligence committee whose report is causing such an uproar now.

Today, partisanship reigns in Washington. For Democrats, it’s not enough to expose the CIA’s tactics, correctly, as inhumane and cruel; these tactics must also be condemned, much more controversially, as providing no intelligence that couldn’t have been gotten otherwise. For Republicans, by contrast, it’s all about exaggerating the benefits of “enhanced interrogation” and playing down the costs, moral and practical.

Those who would argue for a more nuanced view have no true spokesman in Washington, unless you count President Obama. He has banned “enhanced interrogation” and supported release of the Senate committee’ s report (after insisting on redactions), but he eschewed prosecution of the officers involved and defended the CIA and its director, John Brennan, in general terms — while refusing to weigh in directly on whether the agency’s methods, objectionable as they were, helped thwart terrorist plots.

World War II gave rise to a sense of overriding national unity in the face of global threats, a feeling that ebbed and flowed but basically endured through the Cold War — and muted partisan conflict accordingly. The establishment and maintenance of professional, nonpartisan intelligence services (or at least the aspiration to sustain such services), were an expression of that climate.

Some thought that the terrible attack of Sept. 11, 2001, might have a similar galvanizing effect on Americans, their politicians and their national security establishment.

The torture report and the reaction to it represent yet more proof of how false that hope was.

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