Per the American Action Forum (AAF), NATO countries increased their spending in 2016. Some factors in the spending increase are increased Russian aggression on the borders of Eastern Europe (i.e. Crimea annexation and Ukraine’s civil war) and President Trump’s campaign rhetoric about rethinking America’s spending habits as a member of NATO:
…[W]hile 23 NATO member countries increased their defense spending in 2016, only 5 met NATO’s 2 percent spending goal. The Trump Administration has previously assured NATO member countries of the U.S.’s commitment to NATO but has also said that if other member nations do not step up and meet the 2 percent spending goal the U.S. will have to “moderate” its involvement with NATO. The report went on to show that in 2016 member nations had increased their defense spending by 3.8 percent.