precedent is important, and most presidents have opted to follow washington's example in keeping the vp effectively isolated doing nothing in the senate. vp's have at times been selected to lead delegations, sit in on cabinet meetings, open up shopping malls and lead the space program. most of the time the vp is longtime office holder who the party wants to do a favor, or a compromise candidate with the party to keep the president in check. as a result, they're often sidelined because theg don't have a good relationship with the president from the get go.
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