The integrity of the Special Investigation must be protected. It is already alarming that the WH is trying to discredit all media outlets except the one that is sympathetic to him, so we must protect INDEPENDENT, non partisan sources of information. 45 must be blocked from firing or in any other way interfering with Mr Mueller.
Trump, or any Trump allies should not be able to fire Mueller. Trump is unhinged, and becomes more so with every Mueller news story. He can not interfere with the investigation into his alleged bad acts.
We absolutely need these protections in place to prevent a situation where a President could fire special counsel if he didnt like what they were finding. If we lived in a world with more integrity, we might not need something like this, but we don't live in that kind of world so we desperately need this.