You might remember the long campaign to divest in South Africa, then Sudan, big tobacco, Israel. Now divestment is back again on college campuses. This time, the cause is global warming. Over the past two years, student activists at nearly 400 colleges across the US have been campaigning to push their schools to pull fossil fuel out of their portfolios. Last week Pitzer College joined the fray, and students in the UC system are urging their schools to follow suit. There's a significant amount of money at stake, and many asset managers say divestment is financially irresponsible for public universities. They're not alone. Others also believe that divesting is not the most efficient political strategy. We hear different viewpoints.