Waiting on 5G can feel a lot like trying to download Avengers: Infinity War with just one bar of cell service—in a word, excruciating. But after years of hype, fifth-generation wireless technology and the blazing speeds it promises will finally start to roll out this year. The U.S. must ramp up investment to avoid falling behind. According to Internet metrics specialist Ookla, which gathers data through its Speedtest product, as of June the U.S. ranked 47th globally in mobile download speed, with an average of 27.5 megabits per second. U.S. networks are slower in part because of high usage. But since 2015, according to Deloitte, China has outspent the U.S. by $24 billion on wireless infrastructure.