Last Friday I had the opportunity to meet Glenn Greenwald, the best-selling author and Salon contributor who was presenting his report – funded by the Cato Institute – on Portugal's experience decriminalizing personal possession of drugs over the past eight years. Few, even in the drug policy world, have paid much attention to Portugal's remarkable but sensible 2001 decision to remove drug use and possession from the criminal realm and address it solely as a public health issue. The details of Portugal's…