American Checks and Balances Discussion

How well has Congress played its role as a check & balance on the power of the executive branch during the Trump administration and in the previous Obama administration?  To what degree has Congress been able to maintain its institutional autonomy and not be a rubber stamp for the President under conditions of unified government (when both chambers of the Congress are controlled by the President’s party) in the Trump and Obama administrations?  To what degree has Congress been collaborative and not obstructionist or adversarial with the President under conditions of divided government (when one or both chambers of the Congress are not controlled by the President’s party) in the Trump and Obama administrations?  Finally, does partisanship explain Congress’s relationship with the President or is Congress acting from its principles as defined in Article 1 of the Constitution or is there another explanation?  Discuss.  (250-word limit)