Doesn't Copenhagen also structure its traffic protocols around bicycle commuters? For instance, letting cyclists go on a green light several seconds before cars, in order to ensure that nearby drivers can see them?
Copenhagen has done studies [1] indicating that every mile driven accounts for some net economic loss (due to the harmful health effects of sedentary lifestyles, pollution, the cost to the commuter of gas/cars, the cost to society of maintaining automotive infrastructure), where very mile ridden constitutes a net economic gain (decreased healthcare costs due to being more active, lower personal cost of owning a bicycle, etc).
If the US spent more time looking at commuting from an economic and health perspective, we'd probably find that more government action is needed, beyond "Bike to work day"