In the British government, only Winston Churchill saw the ramifications of a communist victory. "It is a delusion to suppose that all this year we have been fighting the battles of the anti-Bolshevik Russians," Churchill said in December 1919. "On the contrary, they have been fighting ours, and this truth will become painfully apparent from the moment that they are exterminated and the Bolshevik are supreme over the whole vast territories of the Russian Empire."

The West's failure of imagination in 1919 ended in disaster. Because Lloyd George could not see beyond the horrors of an unpopular Russian war, he became a midwife to the Soviet Union. Because Woodrow Wilson lacked the vision to see the difference between liberalism and communism, he became Soviet Communism's nursemaid.

Failure of imagination remains the greatest danger facing Western civilization. Today, the left's failure of imagination has infected the body politic with regard to the Middle East. The left's myopic obsession with daily body counts has blinded us to basic truths: Iran is an aggressive power bent on domination of its region. Walking away from Iraq creates a power vacuum Iran will quickly exploit.

We can simply walk away from Iraq; we can ignore the burgeoning threat of Iran. But are we willing to bear the consequences? For 20 years after World War I, Britain and America enjoyed the bounty of peace, even as millions perished in Russia. Soon enough, the Soviets joined with the Nazis to threaten Western civilization. After the defeat of the Nazis, the Soviets murdered with impunity for decades more.

On November 8, 2001, President Bush spoke about the events of September 11. "We have endured the shock of watching so many innocent lives ended in acts of unimaginable horror," he said. It was our failure to imagine the possibility of such horror that allowed it to occur. We must not make the same mistake again.