WASHINGTON — President Trump on Tuesday is to visit a barren stretch of scrubland in San Diego to view eight attempts at realizing his vision for a “big, beautiful wall.” All the prototypes are big. None are beautiful.

The eight stolid slabs awaiting Mr. Trump inside the razor wire in the border neighborhood of Otay Mesa were chosen from numerous proposals (the Department of Homeland Security refused to say how many) submitted to the agency last year. In soliciting ideas, the department said that each prototype would be judged, along with its impenetrability, on “aesthetics and innovative design.”

Innovation they got. Among the unsuccessful bidders was Clayton Industries, a Pittsburgh-based outfit that envisioned a 30-foot wall reinforced by sensors, an electrified chain-link fence and a railroad track dumping nuclear waste into a 100-foot deep moat. The waste is used as a power source.