The fence, with two layers separated by road for border-control vehicles, would run for about 700 miles, at an estimated cost of $1.5 to $2 million-a-mile, in five strategic areas where crossings are particularly frequent. A fence has worked in the San Diego area where illegal-alien arrests have declined sharply since 1996, when construction began. Illegal crossings picked up elsewhere, which critics of the extended fence argue will happen again: A fence will only shift migration patterns.
It is true that a fence can't be the only tool of enforcement, and previous attempts to depict it as the easy answer to immigration lawlessness tended to be cynical. Last week, in contrast, the House passed provisions to make employers verify that their workers are legal, and to increase cooperation between federal, state and local governments. The same people who attack the fence as ineffectual also oppose these necessary measures to integrate it with better enforcement in the interior.
Whatever the fence's ultimate effectiveness, comparisons to the Berlin Wall are offensive. But a certain cast of mind fetishizes objects as such. During the Cold War, Soviet missiles and American missiles were considered equally immoral by arms-control advocates, no matter the differing nature and aims of the governments wielding them. A missile was a missile. Similarly, opponents of a border fence apparently consider any wall objectionable as a wall, whether it is an instrument of repression or a way for a nation of laws to see that those laws are obeyed.
Americans can reinforce and extend their border fence with a clean conscience.