Just because it's common parlance does not mean it's a good practice. HN is supposed to be a forum for reasoned discussion. Any kind of sophistry or propaganda should be called out. Since Trump describes his regime as having an "unprecedented and powerful mandate", and this is actually incorrect in several ways, it is worth drawing the distinction here.

Another way in which Trump is incorrect is that his election victory margin is average among presidential elections in terms of both electoral vote margin and popular vote margin.

I only see the hill article using that parlance. I looked at the articles the hill certainly says half the country voted for Trump. It is an opinion piece you linked to though not a news piece.

The center for politics and global citizen articles do not seem to use half that way though.

For center for politics the title starts with "How the Other Half Votes" and they seem to keep to that usage and never use half of USA/America.

For Global Citizen the title starts with "Half the Planet Will Vote This Year" an they seem to stick to that and never use half of USA/America

262m is the estimate for the "Population of Voting Age for Each State and the District of Columbia". Not all of these are voters, and only malicious thinking could lead to the conclusion that these people are all happy (or unhappy) with Trump.

> When people say that half the country voted for X, it is implied they are referring to voters

In this case it is a very large difference and it is important to keep it in mind, even if starting with 340 million is not the best place to start.

Google tells me the adult population of the USA is ~260 million, so 260 - 77.3 = 182.7 and 182.7/260 ~0.7. So ~70% of the adult population did not vote for Trump. It is part of Trump's job as president to represent and serve that 70%. It is also part of Trump's job to represent and serve the minority of adults who voted him into office too.

I have talked to many people over the years that did not know so few people voted or the difference between majority and plurality. These sort of details can and do lead to misunderstandings, that unfortunately, can and do waste considerable time.