The basics of Republican health legislation, which haven’t changed much in different iterations of Trumpcare, are easy to describe: Take health insurance away from tens of millions, make it much worse and far more expensive for millions more, and use the money thus saved to cut taxes on the wealthy.

Donald Trump may not get this — reporting by The Times and others, combined with his own tweets, suggests that he has no idea what’s in his party’s legislation. But everyone in Congress understands what it’s all about.

The puzzle — and it is a puzzle, even for those who have long since concluded that something is terribly wrong with the modern G.O.P. — is why the party is pushing this harsh, morally indefensible agenda.

Think about it. Losing health coverage is a nightmare, especially if you’re older, have health problems and/or lack the financial resources to cope if illness strikes. And since Americans with those characteristics are precisely the people this legislation effectively targets, tens of millions would soon find themselves living this nightmare.