The proposal for Maryland to become the first state to tax big internet platforms that track how you browse on the internet and target ads at you highlights how much money is made in digital ads. Computer Science Professor Avi Rubin says the more targeted ads, the more money to be made. Opponents contend the tax would hit not just Google and Facebook, but also hurt Maryland businesses. Economist Paul Romer disagrees. He says those arguments are just a big smokescreen.