Portland Is a Problem for Biden

With fewer than 100 days until the election, the main threat to Democrats is overconfidence, which can breed recklessness. For the most part, the Biden campaign has avoided this trap. But on the issue of federal law-enforcement officers in American cities, the presumptive Democratic nominee risks losing his balance.

In response to the demonstrations that broke out after the killing of George Floyd, President Trump decided to rerun Richard Nixon’s 1968 “law and order” campaign. At first, his effort fell flat. Most Americans…