if he doesn’t know the connotations of the words he employs, he should finally learn that the white house would be happy to proof read his tweets (or any person he would like to choose) in case he makes a mistake.

This is easy and standard procedure for talks, ... of big company leaders, politicians, ...

I'd add that if you think that "looters are going to get shot" is code for "black people are going to get shot", you're implying that only black people can be looters. Who's the racist?

"When the looting starts, the shooting starts" is a phrase by Walter E. Headley, the police chief of Miami, Florida, who said it in response to an outbreak of violent crime during the 1967 Christmas holiday season.

Donald Trump was already an adult in 1967 and even if he didn't know this was a dog-whistle for white supremacists.... Facebook doesn't have to amplify destructive ideologies just because the ones who relay it are ignorant. Otherwise everyone would invoke that excuse.

How is this a dog whistle for white supremacists?

When people loot, other people will shoot them to prevent their livelihood from being destroyed. It’s a good phrase to sum up that there is going to be a violent reaction to looting.

Oh, please. Walter Headley is so obscure he doesn't even have a Wikipedia page. The closest he's got is a page for the phrase "when the looting starts, the shooting starts", which wasn't created until after Trump had made his Tweet.

The idea that this is a well-known racist catchphrase which anybody had heard of a month ago is absurd, and you know it.

(For the record, I despise Trump. All I ask is that we keep our criticism of him tethered to reality - it's not like we don't have enough non-fictional reasons to oppose him.)

I would tend to agree but him retweeting a video of someone yelling "White power", clearly and distinctively multiple times does tend to lower the tolerance for any type of catchphrase that has a racist past.