No small feat.
Trump achieved this through his chosen method of communication which is of course Twitter...
Until now it was the modus operandi of the White House to vehemently maintain that Trump was not under investigation and to shout down anyone who implied differently.
But it's right there in the first four words of his very own tweet...
"I am under investigation"
That's pretty definitive.
It was with his remaining twitter characters that he proceeded to throw Rod Rosenstein, the deputy attorney general, to the wolves.
Remember it was Trump himself, during a May 11th NBC Lester Holt interview, that referred to Rosenstein as...
"highly respected -- very good guy, very smart guy. The Democrats like him. The Republicans like him."
What a difference an obstruction of justice charge makes!
Trump tweet tirade comes from the fact that after he fired former FBI Director James Comey the White House tried to float that he did so due to a memorandum Rosenstein had authored as the reason Trump had to do so.
This was of course was proven to be a lie when Trump stomped all over that talking point in the same May 11th NBC Lester Holt interview where Trump praised Rosenstein when he told Holt in no uncertain terms that he was going to can Comey regardless of the recommendation from the Justice Department...
"I was going to fire Comey-- my decision. There is no good time to do it, by the way. I was going to fire regardless of recommendation."
So in reality Trump should be crapping on himself in today's tweet instead of Rosenstein.
Trump's real anger at Rosenstein undoubtably stems from the fact that he personally appointed former FBI Director Robert Mueller as a special prosecutor in the investigation of alleged collusion between Trump associates and Russia.
Rosenstein was in essence the only one who could make the call since Trump's Attorney General, Jeff Sessions, had to recuse himself from the investigation for failing to disclose during his confirmation hearings that he had met with Russian officials no less than three times.
On a final note, back in May, it was rumored that Rosenstein had threatened to quit if the White House continued to maintain that he authored the memo for the express purpose of getting Comey fired. I imagine he now wishes he had done just that.