Some consider President Obama's refusal to attend the commemoration of the 20th anniversary of the fall of the Berlin Wall in Germany next week an outrage.

I consider it a tragedy.

To commemorate, after all, is to remember. And Americans need to remember, not just that the Wall fell, but why it fell. We need to remember that the Berlin Wall was the symbol of more than just the Cold War, more than just the division of Europe.

It was the symbol of an evil ideology that denied human dignity, denied truth, and respected only power.

When the Wall fell, truth and human dignity, in a rare moment in the 20th century, triumphed over power. But that victory is not permanent.

Today, in the 21st century, we are faced with new ideologies that challenge human dignity and regard truth as something they decree. At home, a growing culture of radical secularism declares that the nation cannot publicly profess the truths on which it was founded. Abroad, an irreconcilable wing of Islam believes that the lives of the innocent are expendable.

And so we need to remember why the Wall fell. And it is a tragedy that the president will not lead us in remembering.

Nov. 9, 1989, was the culmination, not the beginning, of the advancement of human freedom and dignity in Eastern Europe.

The crack in the wall that would become a torrent that day in 1989 was made 10 years earlier during Pope John Paul II's historic visit to his native Poland in June 1979.

Thirty years later, it's difficult to grasp what a momentous event this was. As my wife Callista and I recount in our upcoming documentary, "Nine Days that Changed the World," Pope John Paul II was seen in person by an astonishing one-third of the Polish people at masses and appearances across the country.

As he spoke, one by one, he punctured the lies of Communism.

To a people who had been told that they were merely subjects of a supreme state, he said they were children of God who were responsible and free to make choices.

To a people who had been isolated by the ever-present fear caused by the secret police and their multitudes of informants, he said, "Never lose your spiritual freedom."

To the subjects whose leaders propagandized the "benefits" of 30 years of socialism, he told them that they were heirs of a thousand years of Polish Christianity and countless sacrifices by Poles on behalf of freedom and truth.

And during his first Mass in Poland, one million people who lived under a regime that said there was no God, affirmed in spontaneous song "We want God!"

Just 14 months after the Pope left Poland, widespread strikes forced the official recognition of the trade union Solidarity. And from there, the dominos began to fall. First Poland, then Hungary, Czechoslovakia, East Germany, and finally the Soviet Union itself.

The Pope was not alone in this historic struggle for freedom. President Ronald Reagan and British Prime Minister Margaret Thatcher provided indispensible political leadership.

But it was John Paul II, beginning in those nine days, who brought God closer to the hearts of the Poles in a most profound and impactful way, and the result was a country and a world transformed.

He told all the people of the captive nations of Europe and beyond just what the Declaration of Independence tells us: That every man and woman has inherent dignity and possesses certain inviolable rights because we are made in the image of our Creator.

That no government that denies these rights is legitimate. And that an ideology that violates our rights and our dignity is totalitarian in nature, whether it is a democracy or a dictatorship.

The message of human dignity that led to the toppling of the Berlin Wall twenty years ago is a true message of hope rooted in the spiritual nature of man and the freedom to know God.

And so it is a true shame that the President of the United States--this man who cloaks himself in the rhetoric of hope--won't be pausing to remember.

Newt Gingrich is a senior fellow at AEI.