SAITAMA, Japan—After a stunning loss in the opener, the U.S. women’s soccer team vowed to be ruthless against New Zealand. And they rebounded in a big way. The Americans cruised to a 6–1 rout of New Zealand in front of First Lady Jill Biden at the Tokyo Olympics on Saturday. With the United States leading 2–0 at the break, Biden arrived in time to watch the team put the game away in the second half at Saitama Stadium. The United States was blanked by Sweden 3–0 in the opener. It was the team’s first loss since January 2019 and snapped a 44-game unbeaten streak. The Americans had not been held scoreless since 2017. But the Americans vowed to regain control of the tournament. Defender Kelley O’Hara said the United States needed to be “ruthless” against New Zealand. “Sweden was a very good team and we didn’t play our best, and …