Like millions of my countrymen, I am profoundly concerned that the debate over government spending, while necessary, has come to threaten the cultural, educational, informational and civilizing influences that help equip us for enlightened citizenship. Suddenly, these are dismissed as "unaffordable luxuries" when in fact we have never needed them more.

In the midst of the Great Depression, our government managed to fund some of the most enduring and memorable documentaries, photographs, art and dramatic plays this country has ever produced. Our need for such cultured and civilizing influences is no less urgent now.

Difficult decisions will have to be made - but not on the back of an infinitesimally small fraction of the deficit that the National Endowment for the Arts, the National Endowment for the Humanities and public broadcasting represent. These institutions are in their fifth decade of unmatched service. With minimal funding, PBS manages to produce essential (commercial-free) children's programming as well as the best science and nature, arts and performance, and public affairs and history programming on the dial - often a stark contrast to superficial, repetitive and mind-numbing programming elsewhere. PBS supplements the schedules of hundreds of other channels. It produces "classrooms of the air" that help stitch together statewide educational activities and helps create cradle-to-grave continuing education services that are particularly appreciated in rural states. Alaska, Oklahoma, Arkansas, West Virginia are among the states that depend on PBS shows daily, belying the canard that this is just programming for the rich and bi-coastal.

Polls consistently show that huge majorities of all Americans support public broadcasting. And false arguments of bias in public broadcasting often cut both ways; members of the Clinton administration bitterly complained to me about criticism they perceived as coming from NPR. PBS is the place that gave William F. Buckley a home for almost 30 years. In an age when nearly everyone selects their media on the basis of their political views, it's refreshing to have an in-depth option that periodically upsets the powers-that-be in both parties. Our founders would be delighted.

Many say that what can't survive in the marketplace doesn't deserve to survive. Not one of my documentaries, produced solely for PBS over the past 30 years, could have been made anywhere but on public broadcasting. Each time a film of mine happens to reach a large audience, I am "invited" to join the marketplace. Each time I patiently explain to my new suitor what I have planned for my next project - an 11-and-a-half-hour history of the Civil War, perhaps, or a 17-hour investigation of the history of jazz, or a 12-hour history of the national parks - I am laughed out of their offices, sent, happily, back to PBS.

The marketplace can be wonderful. Its relentless forces do weed out many unnecessary things, but there are some things the marketplace cannot do. It won't come to your house at 3 in the morning if it's on fire, it doesn't plow the streets in a blizzard and it doesn't have boots on the ground in Afghanistan. I don't mean to suggest that PBS or the endowments have a direct role in the defense of our country; no, they help make the country worth defending.

In the late 1980s, I had the honor of meeting President Ronald Reagan at a White House reception. I told him I was a PBS producer working on a history of the Civil War. His eyes twinkled as he recalled watching, as a young boy, parades of aging Union veterans marching down the main street of Dixon, Ill., on the Fourth of July. Then, in almost an admonishment, he spoke to me about the responsibility he saw for a private sector-governmental partnership when it came to public broadcasting and the arts and humanities. (His administration was very supportive of these long-standing institutions.) I told him that nearly a third of my budget for the Civil War series came from a large American corporation, a third from private foundations, and a third from the National Endowment for the Humanities, an agency then led by Lynne Cheney. He smiled and then held me by the shoulders, and his eyes twinkled again. "Good work, he said. "I look forward to seeing your film."

Today, our funding model remains essentially the same. But proposals to defund CPB and the endowments will put some of the best stuff on the tube and radio out of business. Somewhere, I imagine, the twinkle would be extinguished from Ronald Reagan's eyes.

The writer is a filmmaker.