I certainly support bringing Mulvaney and Bolton (and potentially Giuliani) in to testify. Hearing from them, under oath, will get us over this issue. These men know first hand what happened. President Trump said they were off limits in the House hearings (thus the obstruction of Congress charge). I this President continues to push (and possinly cross over the legal boundaries) of his presidency, this hearing in the Senate needs full access to these men. President Trump continues to push the legal limits of this nations laws of the office. We have checks and balances in the structure for a reason. The primary defence in the House hearings was that no one had a direct connection; that a lot of the testimony was hearsay. Well, in the Senate - with Judge Steven's presiding - let's go beyond hearsay and force those Trump protected to testify. If he is innocent... then that will be uncovered. If he crossed the line for personal gain.. well that would be proved as well. What I dont find relevant in this particular hearing g is to call the Bidens. That is a separate issue that is worth reviewing (along with the Trump family ties and influence in private/public matters). And, it is a travesty for lawmakers on EITHER side of the aisle to say nothing will change their minds. In the private courts, those folks would be turned down for just duty!