IN A PRESIDENTIAL campaign that starts in Iowa you're going to hear a lot about farm issues, and much of it will sound the same. Candidates praise the family farm as the foundation of Western civilization and hint that there's nothing they wouldn't do to sustain it. The problem, as Congress found when it wrote the 1985 farm bill, is that too much has been spent on farm policies but still many farmers are in trouble. The 1985 bill sensibly started a slow lowering of federal price supports. A few candidates propose radical shifts from current policy. But most candidates of both parties stick to the path Congress chose in 1985.

Bob Dole was an architect of the 1985 bill, and defends it; as a Kansan who has served on Agriculture committees for nearly 30 years, he argues he is more knowledgeable about and compassionate to farmers than anyone else. George Bush cites evidence (there is some) that the farm bill his boss signed is beginning to work, and then moves on to other themes: open up markets abroad, use alcohol fuel at home. Paul Laxalt, who voted for the 1985 bill, wants government to "revitalize" rural America, and Alexander Haig talks of "rescuing farmers from chaos."

The Democrats are fine-tuners. Bruce Babbitt, Joseph Biden (who opposed the 1985 bill), and Tennessee cattle farmer Albert Gore (who voted for it) talk of targeting subsidies at family farmers and excluding others -- a worthy, if elusive, goal. They oppose both production controls and a total abandonment of farm programs. Paul Simon, who with Mr. Biden opposed the 1985 bill, calls for "an agricultural policy as creative and productive as the American farm family." Michael Dukakis says supply management will continue to be necessary, and tries to live down the embarrassment suffered when he told Iowans how Massachusetts farmers were growing Belgian endive.

Radical proposals come from both parties. Richard Gephardt joins Iowa Sen. Tom Harkin in supporting a bill that would allow farmers to vote in production controls, which would increase prices to consumers and make U.S. products less competitive around the world: a terrible idea no other candidate supports. Jesse Jackson, who has been courting farm protest groups, wants a moratorium on farm foreclosures, a restructuring of farm debt, and a return to parity prices: the moon. Jack Kemp says some sensible things about Harkin-Gephardt, and prescribes his own elixir, the gold standard. Pete du Pont wants a five-year phase-out of subsidies. Policy is moving in that direction, but that's gunning the motor way too fast.

As ever, farm problems inspire extravagant rhetoric. But with Iowa farm and land prices rising this year, it's becoming apparent that the wiser course is the one Congress is already on.