Facing one of the final four teams doesn't seem like such an odd possibility to me. I'll probably end up figuring out stats while I'm typing this.
Here's our good friends Mexico in the same 7 tournaments.
1994: Italy (2nd) in group stage, Bulgaria (4th) round of 16
1998: Netherlands (4th) in group stage
2006: Portugal (4th) in group stage
2010: Uruguay (4th) in group stage
2014: Brazil in group stage, Netherlands round of 16 (finished 3rd and 4th)
Another way to look at it would be how many teams in a given world cup end up playing a top 4 team. This year three teams in groups A (Brazil), B (Netherlands), F (Argentina), and G (Germany) played teams in the top 4. In round of 16 there was also Algeria (Germany) and Switzerland (Argentina). In the quarterfinals add Colombia (Brazil), France (Germany), Costa Rica (Netherlands), Belgium (Argentina). That's a total of 18 out of 28 teams. I think the maximum possible is 20 and the minimum is 12.
That math seems right to me. Showing that it should be about 50% of the time. The U.S. is 5 of 7. Well through 50%, although in a small sample it's not as big a deal as it actually looks. The variation from normal is easily accounted for when you consider seeding, as well as increased chances of facing a final 4 participant as the group runner-up (or worse for 1992) as opposed to the group winner. And no, the odds of facing a final four team, especially for a team getting out of their group roughly 50% of the time, is not completely unusual, it's just a bit unlucky.
It does get a bit worse when you consider the U.S. has faced a final 2 team in 4 of 7 tournaments, something that seems extremely unusual. But, as with all small sample sizes, that skews as well. It is also possible the U.S. will face the champion in 3 of 7 tournaments, provided Germany wins Sunday.