Pundits and commentators in New York City and Washington, D.C. think that when president-elect Trump declares he will “drain the swamp”, he’s either expressing racism (Ray Lenz of the Southern Poverty Law Center) or wasting time since “it just rains and then there’s another swamp” (John Podhoretz of Commentary magazine).

If these are examples of respected political and cultural opinion, our nation’s I.Q. has dropped into a sinkhole.

Rather, PEOTUS is using a time-honored metaphor to describe a way to acquire civilization’s most essential need: tillable land with friable soil.  Without it, settlements are condemned to eek out food from local subsistence patches.  Say goodbye to agriculture and a sound rural economy.  Goodbye to towns and cities.

Once swamps were everywhere in the U.S., left by the recession of the glaciers.  Huge swamps covered everything, including areas now occupied by cities and towns, especially those near rivers, lakes and oceans.  Most of the Midwest was shallow swampland.

Let us take Mr. Trump literally.  By draining swamps, we uncover land soaked for thousands of years by deposits of minerals and organic debris.  We open it to sun and air, creating some of the world’s richest farmland.

Khrushchev admired my native Midwestern soil, likening it to his own Soviet Russian soil.  Because both continents were covered in glaciers for millions of years, the land is still trying to work out where to put all the melted water.  Meanwhile, the greatest soil fertility in recorded history is enjoyed by both countries.  This is not the subject of trite dismissals from the chattering class.  Indeed, a more powerful, life-giving injunction is hard to find than, “Drain the Swamp!”

The other problem with swamps is death.  We get “miasma” from the Latin word for the misty, vaporous stenches that waft often from swampland.  Our ancestors thought this air pollution caused many fatal diseases.  They were only half-right; it was the mosquitoes that thrive in standing water—and swamps have that aplenty—that were killing everyone by the diseases they spread—malaria and yellow fever to name two.

Walter Reade, for whom the famous military hospital is named, contracted malaria playing along the Potomac.  Similarly, boys and girls—north, south, east and west—caught it.  Nothing “racist” about it.  Mr. Trump’s metaphor, thus, has a long history of filling his listener’s nostrils with ominous meaning.

Literal swamps, such as D.C. once famously was, are drained by digging deep trenches through them.  These are graded outward and downward from the swamp’s wettest areas.  Once that is done, “tiles”—large sections of pipe—are laid to comprise one long pipe.  They are called “tiles” because they are made of the same type of cement used originally to make paving tiles.  Today plastic pipe is used, but the name, “tiling”, stuck.

D.C.’s many quaint channels still direct water from the congested areas into the rivers.  Drive through the countryside anywhere in the U.S. and see ditches along the side of the road next to farmers’ corn, soybean or vegetable fields.

Done correctly, swamp draining is permanent, as in D.C. and farms and gardens throughout the nation.  Buildings stop sinking.  The dry land changes the types of plants that grow—no more roots being drowned in water.  No rain fills the swamps up again, as Podhoretz incorrectly opined.

“Planning is everything”, said a great former general, President Eisenhower.  If president-elect Trump wishes to correct our country’s many ills, as well as dispel the “miasma” and similar misperceptions afoot, he needs, more than anything else, a strategic plan.  What to drain and how to do it?  What needs are most essential, which solutions most virtuous?  Every farmer and gardener, facing a swampy property, knows that without a good strategic plan, you are, in a word, sunk.

A version of this article appeared in the December 26th, 2016 edition of The Wall Street Journal