The leader of the United States encouraging law enforcement and the military to shoot American citizens for looting, that's the line.
Which I agree with to some extent, you're not innocent of a crime because you convinced a person to harm another, just because you were too cowardly to get your hands dirty yourself.
But the US is rather famously not British, so I'm not sure if it's a relevant thing to add to the discussion.
1. Please don't loot, it escalates violence and people will get killed
2. Let's kill all the looters
Whether it's Trump or Ghandi, we're imagining we know something about the internal state of the speaker's mind that we don't know.
* "the Military is with [the governor]"
* "any difficulty and we will assume control"
* "when the looting starts, the shooting starts"
There's a clear causal relationship between these three statements, this is not a plea for peace, it is a threat of violence.
Regardless, all that's in evidence is the federal government is going to back the state and if this keeps going people are going to die. Anything else is something you've imagined/projected into someone else's mind.