Yes, we have another one of those exhausting "What did Donald Trump really mean?" stories — this time, with higher stakes than usual.

As you've surely seen by now, Trump said this about Hillary Clinton at a rally in North Carolina: "If she gets to pick her judges, nothing you can do, folks. Although the Second Amendment people — maybe there is, I don't know.”

Trump's campaign insists he was talking only about political action, not an "assassination." Whatever — that's not how the shocked man behind Trump onstage at the rally seemed to take it.

It doesn't really matter what Trump meant. It matters what he said — a reckless comment that might or might not be outrageous, depending on your interpretation. This has happened over and over during the campaign, and it would happen, with much higher stakes, during his presidency.

What the president says matters. Presidents' comments can move markets, create policy, inflame foreign tensions, and even start wars. It is therefore important that presidents be careful.

Donald Trump is incapable of being careful. His loose talk is not a mere personality quirk and it is not refreshing — it is a reason he cannot handle the job of the presidency.