To make a big difference you need to be social and political.

Going vegetarian makes a tiny difference. Tirelessly badgering everyone you know until 10 of them go vegetarian makes a difference 10 times as big.

Convincing 10 or 50 people to call their senators/reps about putting a price on carbon could have an impact an order of magnitude larger.

Lawmakers listen to their constituents when there is sufficient unity of thought among the constituency. And it has to be regular people that cultivate that unity of thought, through constant discussion of the problems and solutions with everyone they know.

...Now I just need to start to practice what I'm preaching...