What Pat Moynihan once called the Party of Liberty lost one of its most energetic friends last Saturday when Penn Kemble breathed his last after a valiant battle with brain cancer. The Democratic Party, too, lost a friend in Penn. What kind of man was he?

In his college days in 1964, inspired by the civil rights cause and the cause of social democracy, he got himself pictured on the front page of the New York Times, blocking Triborough Bridge traffic in protest of school conditions in Harlem. He and his compatriots in the East River Congress of Racial Equality were about to be hauled off to the calaboose.

His mother, picking up her copy of the Times back home in Lancaster, Pa., was shocked. She would not be shocked many more times by Penn. Ever the friend of racial equality, labor unions, and all the elements of democracy, he moved to the more peaceful protests, not out of timorousness but out of his commitment to reasoned debate. No one could ever question his courage, but he was an eminently reasonable man.

The last time I saw him on his feet was a few months back. He was competing at his favorite sport, handball. To my astonishment, however, he was wearing a helmet. Was this one of his jokes? Penn had a puckish sense of humor, but this was not one of his jokes. After an unexpected grand mal seizure, doctors had drilled into his skull and removed a tumor. That would not stop him from driving a handball 50 miles an hour on the court against those of us who wanted to beat him. Penn was a very tough guy.

His toughness was behind all the political activities that filled his life along with his high intelligence. In 1972 he was a founder of the Social Democrats, USA. He became a Scoop Jackson Democrat, campaigning for the pro-defense anti-communist senator's doomed attempt to wrest the Democratic presidential nomination.

Aware that the McGovernites were shanghaiing the Democratic Party into a lala land of anti-Americanism and narcissistic utopia, he became executive director of the Coalition for a Democratic Majority. Had the CDM taken control of the Democratic Party in the 1970s, it would have remained on the path hewn by Franklin Roosevelt and Harry Truman. It would have remained a vibrant center of American values and avoided much of the foolishness that has led to its decline.

CDM's efforts proved futile and liberal Democrats such as Jeane Kirkpatrick and William Bennett drifted to the Republican Party. Penn remained a Democrat to the displeasure of his old friends, who were now being called neoconservatives. Doubtless that hurt Penn, but he was committed to the Democratic Party and the trade union movement. However, like his friend, the philosopher Sydney Hook, being a Democrat did not prevent him from vigorously fighting communism.

He was with the Reagan administration heart and soul in advancing democracy in Central America. That offended many of his fellow Democrats, but Penn was his own man. He made neocons uneasy. He angered the Democratic elite. But he followed his conscience and continued to establish organizations opposing tyranny and intolerance worldwide. When the Clinton administration made him deputy director of the United States Information Agency, it made a shrewd choice.

In all the years I knew Penn, he kept everything in perspective. In a city, Washington, and a pursuit, politics, where baseness is often the norm and too often the key to power and fame, Penn has been the soul of honor, intelligence, and all the virtues of the timeless liberal. He achieved great things for human rights and the dignity of working people but never drew attention to himself or did anything cheap. There was a "tough guy" quality to his speech, which I always relished; for though he really was a tough guy, he was always the perfect gent.

We never had a cross word in any disagreement. We had many ironic and amusing words. In sum, I rise to say that Penn is one of the finest men I have known. He is one of the guys you would want with you in the foxhole during any battle. There he would get to the business at hand, accomplishing it with a few gruff laughs thrown in. Once the shrieks and whines of the present Democratic leadership are abjured, sensible Democrats will realize that Penn Kemble's life is the blueprint for the Democratic Party's return to relevance.

Mr. Tyrrell is the founder and editor in chief of The American Spectator, a contributing editor to The New York Sun, and an adjunct scholar at the Hudson Institute.