It took far too long, but Europe is finally getting serious about military spending. This summer, at NATO’s most recent summit in The Hague, member states agreed to increase defense spending substantially, to 5 percent of GDP, within a decade. That decision was long overdue. For decades, successive administrations in Washington had urged the continent to do more for the common defense. But it took Russia’s war of aggression against Ukraine, coupled with the Trump administration’s strong-arm