How the U.S. can advance even with a loss
If the U.S. wins or draws they move on. It’s that simple. Sitting on four points to Portugal and Ghana’s one apiece, the U.S. can still move on if it loses to Germany, while Ghana and Portugal draw. (A draw only earns one point in the group table.)
Should the U.S. lose and either Ghana or Portugal emerge with a win, then things get a little more complicated. The U.S. and the the winer of Ghana-Portugal would be tied in the table at four points apiece, meaning goal differential would be the next decider of who moves on. The U.S. sits two goals up on Ghana and five goals up on Portugal.
Say the U.S. loses by one and Ghana wins by one. That puts the U.S. and Ghana even on goal differential and puts the group-stage’s second tie-breaker in play: Total goals scored. The U.S. has four goals to Ghana’s three, so Ghana winning a high-scoring game with the U.S. losing a low-scoring game would be sketchy.
Same goes for a U.S. loss and Portugal win, technically — but the wide goal differential there makes Ghana a much, much more serious threat to American hopes of moving on. If the U.S. and Ghana tie on points, goal differential and total goals scored, the U.S. wins by virtue of the World Cup’s third tie-breaker: Head-to-head result. If that happens with the U.S. and Portugal — who, of course, tied — it essentially comes down to a coin flip.
So, loyal USMNT supporter: Root for a U.S. win (duh). Then root for a U.S. tie. Then root for a Ghana-Portugal draw. Then root for Portugal, but not too much.
But this is America, gosh darn it, and we play to win. Go USA.