Yes, as it should, because unless you want to go into specifics there is no statement both true and general that you can make.
Note, though, that the “standard” view says “no failures of the US are caused by any characteristics of races and cultures” (with the possible exception of white men being just evil) :-/
Then it becomes a trivial statement, the scope of “some” being adjusted to the preconceptions of every individual reader.
Yes, as it should, because unless you want to go into specifics there is no statement both true and general that you can make.
Note, though, that the “standard” view says “no failures of the US are caused by any characteristics of races and cultures” (with the possible exception of white men being just evil) :-/