>What’s going on here, on Trump's hand?
I'm sorry, but I am going to say it was a chemical attack due to the brown color, which seems to be a fungi. The hand would not bruise up to the cuff from handshaking but when someone has grab his hand with their non shaking hand. To me, it seems like a cyanide attack because of the pinkness. It was probably diluted to a degree, so it could be easily washed off by the perpetrator. Regular blood trauma goes from pink, to purple, then to black if it does not wash away like a normal black and blue. President Trump, try using something with a strong propylene glycol in it. If it removes the brown, then it was a fungi attack. Cyanide tends to dry an area. Brown is an indication of a fungi or cyanide as the blood vessels die and the blood starts to coagulate into darker colors. Other signs include swelling after the knuckles on the first flange, relief from cracking that reduces swelling, fingertips tingle. Let us know, because the longer you wait, you will suffer n the cold down to the bone.