It's still a few months before the US U-17 Men's National Team is called on to play fully competitive matches. The 2017 CONCACAF U-17 Championship is - as its name suggests - next year: it starts on April 21. If the young Yanks get through that tournament (which is expected, not least because they have spent much of the past three months handily beating regional opponents), then they will progress to October's 2017 U-17 World Cup.
Competitive play might be a long way off, but there is competition for places in the squads for those tournaments, and some of that is settled by performances in the friendlies that will be played along the way.