I’m not necessarily disagreeing with the checkpoints, but this seems like an oversimplification of the issue. If we say it is constitutional then theoretically we’re also approving other warrantless searches such as the random stop and frisks enacted in NYC under Rudy Guliani. Both are examples of search without probable cause. It’s one thing to argue that the value of increased safety is worth the price, and any court can arbitrarily approve one and not the other, but you have to admit that it’s an end justifies the means policy. In that light I at least understand why people are apprehensive about it.