Originally appeared in the San Francisco Chronicle

On Tuesday, a five-year review of the CIA’s detention and interrogation program was finally made public, drawing back the curtains on a very dark period of American history. The purpose of making this report public is simple: to ensure something like this can never happen again.

The 500-page executive summary that was made public is part of a larger 6,700-page review of a CIA program that included clear examples of torture, far outside the bounds of American values.

It’s important to remember the study is based on CIA’s own records: 6.3 million pages of the CIA cables, memos, reports, e-mails and other documents. These records from the very time the actions took place — appear extensively in the report’s 38,000 footnotes.

Many of these records were disturbing, at times deplorable.

But there was also some wisdom in those records, like a 2005 e-mail from then-CIA Inspector General John Helgerson. It read, in part:

“We have found that the Agency over the decades has continued to get itself in messes related to interrogation programs for one overriding reason: we do not document and learn from our experience — each generation of officers is left to improvise anew, with problematic results for our officers as individuals and for our Agency.”

This report provides that documentation, and now we need to learn from it and apply the lessons.

We must never again allow our country to veer so far off course. To do that, we have to study where we went wrong.

Sen. John McCain, R-Ariz., said last week on the Senate floor, “The truth is sometimes a hard pill to swallow.” Indeed, the executive summary includes some particularly vile treatment, and it’s difficult to comprehend what happened. We included these details to drive home how wrong and un-American this program was.

One detainee was kept awake for 180 hours — that’s more than seven days without sleep. One otherwise healthy detainee died while in custody, likely from hypothermia.

Beatings were common, painful stress positions were often used and threats were made against detainees’ lives and against their families. There were even mock executions.

All of this happened outside the normal system of checks and balances. Congress was blocked from oversigt, and policymakers reviewing the program were often misinformed. What guidelines existed to prevent abuse were repeatedly ignored.

The result of these actions? A program of interrogation and torture that yielded no information necessary to stop terrorist plots or capture terrorists.

This was an ugly program, but let me be clear: Our country is strong enough to own up to what we did and make the necessary changes to make sure it never happens again.

It’s what the most powerful country in the world should and must do.

Lindsey Graham, a Republican colleague from South Carolina who also spoke on the Senate floor on Tuesday, made this point: The evils our enemies visit upon us are far worse than how we treated these prisoners, but we must hold ourselves to a much higher standard than ISIL or al Qaeda.

This isn’t about our enemies. This is about us.

So now we need to move forward. It’s time to finally enact federal laws that ban interrogation techniques like these from ever being used again.

In the coming days, I plan on joining several other senators in offering a series of recommendations that stem from this report. We shouldn’t have to rely on a presidential executive order, which could be reversed and is the only thing prohibiting the CIA from resuming this program.

Critics of this report have said that releasing it will make us less safe, that the world is too unstable to handle what this report found. In considering these concerns, I determined that there is never a good time to admit we tortured people, but it must be done.

But it’s not the report that’s at fault, it’s the fact that we allowed torture to happen in the first place.

When we released the report, I talked on the Senate floor about how the study was conducted, what was in it and what it meant.

But the speaker who followed me really put it in the proper context, and that was Sen. McCain.

No one knows better that torture doesn’t work than John. He spent five years as a prisoner of war. He lived this debate, and I’m proud to have him on my side.

John spoke eloquently, offering argument after argument against the use of torture.

One passage in particular stuck me:

“It is essential to our success in this war that we ask those who fight it for us to remember at all times that they are defending a sacred ideal of how nations should be governed and conduct their relations with others — even our enemies.”

Let’s not forget that lesson. Let’s not repeat the same mistakes. I encourage everyone to read the report, come to your own conclusion and if you agree, join in the fight to end torture.

Dianne Feinstein represents California in the U.S. Senate.