It happened in 2013 for the last time: the US women’s team lost a knockout game at a FINA event.
They went down against host Spain in Barcelona, at the Worlds’ quarter-finals – a bit shocking result a year later when they had claimed their first Olympic title after a long wait (though it crowned a great run when they won 8 out of 9 FINA events between 2009 and 2012).
Since then – no stopping. It started in 2014 by winning another edition of the World League Super Final – and once they got going, they came first at each and every major. It’s 14 gold medals in a row: 2 Olympics, 3 Worlds, 2 World Cups and 7 World League titles. En route, they barely lost a game, usually one or two per year but when it really counts, in the knockout phases no one could really impose any threat on them.
This year they already ticked the annual loss, in the WL International Tournament against Australia – so we may see the usual storm. Indeed, at the last two editions they won all six matches on both occasions, since their last loss to Italy in the group-stage in Kazan 2015, their winning run at the Worlds stands at 16 matches…

The US dominance is getting more and more overwhelming, they got the most titles (6), the most medals (9), the most semi-final appearances (11), and the longest medal winning streak (4) and the most consecutive appearances in the finals (3, the latter two are tied with Italy).
While they almost won half of the titles in the 14 editions, the remaining eight went to six nations, Italy and Hungary claimed two apiece, the Netherlands, Australia, Greece and Spain won once. Five medals landed in Italy (four in a row), Australia and the Netherlands, while Russia had the second most semi-final appearances, though a bit amazingly they lost all their eight semis (never made it to the gold medal match), came off with five bronze medals. For the well-known reasons, they won’t have a chance to have another try this time.