As we mark the 20th anniversary of the fall of the Berlin Wall, the emphasis should not be on speeches and ceremonies but rather on the lessons of the fall of communism for the war on terror.

Although they seem different–one claims to be religious whereas the other was, supposedly, a perfect science–communism and political Islam are essentially the same.

Both are radical ideologies that divide the world into the elect and the profane. Both deny individuality and suppress free will. And both treat man-made dogma as infallible truth and seek to impose it by force.

Secretary of State Hillary Clinton recently reacted to a question about ideology by saying, “That’s so yesterday.” Nothing, however, could be further from the truth. The drive of an ideology to apply a false idea on the basis of its own inner logic independent of external reality is a mortal threat to the West and will be for generations to come. Accordingly, the experience of communism can do the world some good–if its implications are understood.

The following lessons of communism could prove vital to the West in the war against radical Islam:

The challenge must be confronted at the level at which it is posed.

An ideology is a system of total explanation. It rejects universal morality and insists that right and wrong are determined by the interests of a specific group–the proletariat, the master race or the ummah. In effect, the adherents of totalitarian ideologies deify themselves, even if they pretend to be “religious.”

Our response to the claims of totalitarian ideology is traditionally to defend freedom. By answering

an ideology that claims infallibility and promises to create heaven on earth

by defending “freedom,” however, we immediately raise the question of “freedom for what?” We also leave the contents of the ideology completely unchallenged. The failure of the West during the Cold War to challenge the claims of communist ideology was always taken by the communists to mean that the West did not believe in anything.

In fact, it is necessary to confront the terrorist ideology directly. Instead of treating freedom as an alternative to ideology, we need to attack radical Islamic ideology as an insult to sanity. It needs to be pointed out that supposedly religious Islamic radicalism is based on man-made dogma and that it relies on the same psychological mechanisms and has the same results as atheistic Communism and Nazism. It is only by attacking Islamic radicalism as an idea that we avoid the impression that the terrorists’ interpretation of themselves is implicitly accepted. At the same time, by attacking radical Islam as based on false values, we automatically call attention to our own. In the Soviet Union, it was often noted by pro-Western Soviet dissidents that “it is difficult to beat something with nothing.” Our task is to make explicit that the West stands for universal values, and those values are “something.”

Forget about “right” and “left.”

For years, attitudes toward communism in the West were heavily dependent on considerations of domestic policy. Those who liked the idea of free medical care and guaranteed employment tended to sympathize with communism. Those who were opposed tended to be anti-communist. But in both cases there was little awareness that the real issue was not the communist social system but the attempt to redefine morality and zombify the personality. The split between left and right in the West in relation to communism was manipulated by the Soviets and left us divided in facing a common threat.

There is little risk that radical Islam will evoke sympathy from either the right or the left in the U.S. But there is a danger that tactical disagreements on how to wage the war on terror will take on a partisan coloring. As the experience of communism shows, venomous internal disputes weaken the resolve of the country as a whole.

Treat the war on terror as the nation’s highest priority.

Nazism and communism were defeated with comparatively little loss of American life. The reason was that it was the Soviet Union, not the Western allies, that defeated Nazism at a cost of 27 million dead. The Soviet Union then collapsed without having to be fought. The worldwide cost of the communist “experiment,” however, was about 100 million lives–and this does not include those killed by the Nazi regime, which appeared, at least in part, as a response to communism.

Under these circumstances, the U.S. cannot afford to underestimate the potential of the totalitarian ideological mentality. Voices in the U.S. have warned that the cost of fighting Islamic extremism threatens President Obama’s reform program. History, however, shows that no reform Obama can envisage is remotely as important as neutralizing ideological fanatics who could get access to weapons of mass destruction. The U.S. cannot count on being lucky again.

Don’t lose–ever.

Man-made ideologies, lacking genuine spiritual roots, depend on success for their credibility. This applies also to radical Islam, which claims to have a long time perspective. In the 1970s and 1980s, Soviet citizens, despite their poverty, viewed the world with great equanimity. Eastern Europe was socialist and the revolution had triumphed in Vietnam, Cuba, Nicaragua, Grenada and, so it seemed, Afghanistan. The worldwide victory of socialism appeared to be only a matter of time.

In 1983, however, the U.S. overthrew the communist regime on Grenada, an island of 100,000 persons. The action was widely ridiculed at the time, but it represented the first time that a communist regime had ever been displaced. The unthinkable had become thinkable. It was followed by the Soviet withdrawal from Afghanistan, the collapse of the Soviet empire in Eastern Europe and the breakup of the Soviet Union itself.

Like the Soviets, the Islamic radicals promise their adherents an inevitable eventual victory.

Their confidence was shaken in Iraq but has been renewed in Afghanistan. In this respect, the argument over the link between the Taliban and al-Qaida is irrelevant. They share the same ideology and a victory for the Taliban is a victory for the system of thought that was responsible for the terrorist attacks on the U.S. It will also lead to a surge in support for radical Islam in the Muslim world, which, at the moment, has very few psychological defenses against it.

In dealing with an ideological opponent, haggling and temporizing will not work. We must show the fanatics that they cannot win because we will not lose. In the long run, it is determination as much as military power that will make our victory possible.

David Satter is a senior fellow at the Hudson Institute and a visiting scholar at the Johns Hopkins University School of Advanced International Studies. He is the author of Age of Delirium: the Decline and Fall of the Soviet Union (Yale), which is being made into a documentary film.