The Republicans have a majority and they control what happens in terms of investigations, witnesses, subpoenas, and hearings. Democrats are stuck just speaking up. The danger for both parties and the country is if the Republican were to use their control to suppress the investigation or cover things up or distract the news away from issues with Trump instead of getting at the facts. I see it as a positive that the leadership of the Senate and of the House are today taking a calm and responsible position of letting the facts come out (i.e., not trying to hide, delay, or reshape facts). The Democrats and the news media can act as watchdogs if the Republicans do not work in a bipartisan way or attempt to shape things to favor Trump or the Republican Party.