What did Donald Trump do today?

He got angry that "the media" wasn't reporting a statistic he apparently heard while watching TV news.

Trump claimed that the national debt had decreased by $12B in his first month, compared to an increase of $200B in President Obama's first month. If it's true that other "media" are not reporting this fact, it is probably because presidents in their first month of office have virtually no control over the national debt, which is determined by the previous year's budget. 

Put another way, if Trump really believes a monthly decrease in the national debt is always a sign of good presidential leadership, he is essentially arguing that he took over from a better president than President Obama did. 

The specific numbers Trump cited are slightly inaccurate, but they match what a guest on Fox News had said minutes before Trump tweeted about it. This is not the first time that Trump has uncritically given the presidential seal of approval to things he hears on TV. Advocacy groups have even begun staking out the shows Trump is known to watch in the hope of appealing to him directly via ads. That said, it's not clear why Trump thought "the media" was failing to tell people things he learned from the media.

Why should anyone care about this?

• The president's actual economic advisors should have more influence on his economic knowledge than TV pundits or ad buyers.

• It's bad if a president is more concerned with how he looks in the press than how well he is governing.