It would be easier to isolate causes if the problem were confined to a handful of places. But last year’s increase runs the gamut from mostly white smaller cities to large multi-ethnic ones. It is hard to find a wider cross-section of urban America than Philadelphia (40 per cent), Houston (42 per cent), Denver (51 per cent) and Washington DC (19 per cent). Yet they point the same way. Most also had significant homicide increases in 2019. This year is already worse than last. Community leaders across America are bracing for a long hot summer. Democrats are bound to take most of the heat, but the blame should be shared. The Republicans’ refusal to consider even the semblance of gun control remains serenely unshaken by mass shootings, which have soared this year. Their default response is “thoughts and prayers” — and even more rights for gun owners. It is surely no accident that the nation’s era of falling crime, which began in the 1990s and bottomed out in 2014, coincided with a 10-year assault weapons ban. The measure was contained in a 1994 bill co-sponsored by Biden, then a Delaware senator. Apart from a possible tightening of background checks, Biden looks unable to persuade this Congress to pass serious gun control. The Republicans’ dislike of police reform is another recurring problem. One reason that relations between communities and law enforcement have become so dire is because so many minorities do not trust them.