While presidents can exercise the veto to influence Congress does the use of veto power signal executive weakness or undermine relations with Congress?

Answer 1

If a president's political party has control of both houses of Congress, a veto can signal his inability to control his own party members and the flow of bills passing both houses. It can also signal a lack of leadership ability that would presumably allow him to guide legislation he wants regardless of who controls Congress. On the other hand, veto could be signaling independence from party machinations.

Vetos can undermine relations by blocking laws that Congress wants. On the other hand, if the Senate cannot muster the 60 votes needed to override a veto, it could be a sign that the law was ill considered in the first place and that the veto was an attempt to really get them to reconsider what they were thinking.