That of course is your right, and the right of every voter. Ralph Nader likewise says that he has no regrets, and disclaims any responsibility for the appointments of Justices Roberts and Alito.

[Edit] On conscience: One can argue that it is worth taking a bath in year x for gains in year x + y; the Goldwater enthusiasts of 1964 thought that the debacle contributed to the election of Reagan in 1980, and may have been right.

On 2000: I still argue that Nader had more to do with the elections outcome than any imbalance in charisma.

[Edit 2: yes, I said Scalia...]