This is especially true at the local level. Banning guns from one city makes about as much sense as banning them on one block.
It's hard enough to halt the flow of guns over international borders, where governments police traffic. It's impossible to stop them from crossing municipal boundaries -- which are unmonitored, undefended and practically invisible.
Tens of thousands of cars enter Washington and Chicago each day from places where guns are easily and legally obtainable. Any of those vehicles could be transporting a carton of pistols to sell to willing thugs. If you're on an island, you're going to get splashed by the waves.
The proponents obviously knew all along this city-by-city approach had serious shortcomings. But they figured it was bound to curtail gun availability somewhat. They also hoped that by prohibiting handguns in one place, they were beginning a bigger process.
First, they expected that other cities and states would follow suit. Second, they wagered that strict controls at the local level would acclimate Americans to new regulations at the national level.
But things didn't work out that way. The persistence of crime in supposedly gun-free zones didn't build support for broader gun control by showing the limits of piecemeal legislation. It weakened the case, by proving that such regulations have little impact on the people who present the biggest danger. Instead of a broad upward avenue, it was a dead end.
Gun control supporters fear that if the Supreme Court invalidates local handgun bans, the consequences will be nothing but bad. That would be easier to believe if the laws had ever done any good.