During the 2016 campaign, the biggest concern about President Trump almost always boiled down to one thing: his temperament. Even people who liked Trump had a problem with it. Polls regularly showed that more than 6 in 10 registered voters said he didn't have the right personality and style to be an effective president. Just weeks before the election, 62 percent said he didn't have this baseline quality, according to a Washington Post/ABC News poll. He won anyway.

Trump has now been president for six months, and he's had ample opportunity during that time to prove people wrong. He's taken foreign trips, responded to crises and delivered a well-received speech to Congress.

And yet, Americans may now see him as even less presidential than they did before. A new Post-ABC poll shows a whopping 70 percent of Americans describe Trump as acting “unpresidential.” Only 24 percent say he's acted in a way that's “fitting and proper for a president of the United States.”

Previous polling on this question focused more on temperament to be president rather than the amorphous idea of presidentiality, so it's not quite an apples-to-apples comparison. But it was rare that 7 in 10 Americans ever questioned his temperament. After Trump won the GOP nomination, polls from the Post-ABC, Monmouth University, CBS News polls regularly showed between 61 percent and 67 percent said he didn't have the right temperament.

Today, practically speaking, that number is now 70 percent. Even Republicans are surprisingly split on this question, with 54 percent saying he's acted in a way that's fitting and proper, and 38 percent saying he's acted in a way that's unpresidential.

The Post-ABC poll also took the question a step further, asking whether people believe Trump's unpresidential behavior is damaging or not. A strong majority of registered voters — 56 percent — say Trump's behavior isn't just unpresidential but is “damaging to the presidency.” Even about 1 in 5 Republicans — 18 percent — agree.

This remains Trump's biggest liability as a president. Polls have regularly shown the most negative views of him have to do with his personality rather than his policies. A Gallup poll last week showed 65 percent of people who disapproved of Trump and were asked why cited something about his personality or characteristics; only 16 percent cited policy and only 12 percent cited his job performance.

It was basically reversed for President Barack Obama at this point, with just 14 percent pointing to the man and 65 percent to his policies.

The question Trump and his advisers have to be asking themselves, then, is how much better he would be doing if it weren't for all the tweets and the feuding and the misstatements? The most charitable analysis is that Trump does all of this to get the media worked up, thus reinforcing his strategy of pitting his base against the press.

But when 7 in 10 Americans and 38 percent of your own party thinks you've failed on a very basic quality of being presidential, after six months, you have to wonder how much that strategy — if it is a strategy — is paying dividends.

Trump has had six months of president-ing to prove he's presidential. He's failed on the most basic of tests.