Greg Mankiw notes that President Bush is considering some form of road pricing to reduce congestion. London has a congestion charge which deeply divides opinion. Today, horrifyingly, the administrators of the charge received a letter bomb. CEI actually strongly supports dynamic road pricing (as in, for example, HOT lanes), but recognizes that there are trade-offs involved in all such moves. The key should be that the scheme is based on increased convenience for the consumer, not on convenience for government. The London charge is an example of a badly thought-out scheme that puts the needs of government before the needs of citizens. If any presidential scheme repeats that error, it would not be surprising if it became the focus of resentment.