If you were Al Gore, what would you do?

Iain Murray has a rather snarky post about Al Gore’s environmentalism, implying that Gore just won’t stop until “we are all, every last one us, as completely dedicated to global warming mitigation as he is.” In some circles this is called passion for a cause; in conservative circles I suppose it is called what, annoyance?
The simple question for Murray is this: what would you do if you were Al Gore? If you’re passionate about a cause would you stop just because it hasn’t achieved the traction you’d like to see? Would you be a quitter?