The download sites are all in developing countries where the books are not available except by import that would cost 10X or more US buying power relative to price.

In other words, I lost very little income to piracy despite publishers no longer bothering to try to take down piracy sites. In fact it's an open question if piracy helped sell more books because of engagement from readers in developing countries I would not have reached but for piracy.

The explicitly stated purpose of the copyright clause is not to protect "your lucrative concepts." It is “To promote the progress of science and useful arts," a collective benefit. So if optimal promotion of "science and the useful arts," not commerce, notably, means setting the terms to short, very short, or zero, that's perfectly legal.

Just because you aren't protected by the government, doesn't mean you can't protect your inventions through secrecy.