What is illegal about President-Elect wanting his own private line with Russian counterpart?

All this Democrat mud-slinging is sour grapes, and will weaken the Presidency and the USA. 

America emerged as a second rate power after 8 years of Obama, and a third rate power in 8 years if Democrats keep on weakening Trump further. 

Forget about Trump impeachment. He is no dumb Nixon. In anycase, after his 8 years Trump will emerge richer that Bill Gates. Now that is smart politics.