We could be looking at a classic case of groupthink [0]. I've read a lot of political speeches with half-truths to try and gain an advantage, but the Twitter statement stands out as something that might be their honest take. Someone, probably a couple of someones, with high intelligence and communication ability was in such a state that they interpreted the Tweet as inciting violence.

[0] https://en.wikipedia.org/wiki/Groupthink

A simpler explanation would be confirmation bias.

Regardless, I dont see any sense in it. I wonder if anywhere he can defend it.

I can. The idea is that he’s signaling that an attack on the inauguration won’t injure him, and so it’s mafia talk for “attack the inauguration”.

I don’t support this as a grounds. It’s so flexible that you can see or not see it at will, so, you can give a charitable read to someone you like or a threatening read to someone you don’t. It also relies on mind reading.

Nevertheless a lot of people can read it that way.