The chief issue is whether the bill will help or not. Carlin's article doesn't refer to bilingual education policies: their supporters claim they make the bill redundant; their opponents query their success. Nor does the article refer to the economic issues: the bill's supporters claim a multilingual policy is expensive, and impossible to implement if all 329 of the USA's languages are to be respected; the bill's opponents claim that to implement and police an official language bill will be expensive, and may be impossible to implement.
But could this happen here? English is not an official language in this country either. Will there ever be a "UK English" movement to counter perceived threats to the language? It seems unlikely, given that (pace Wales) there is no Mexico to fuel the kind of anti-English movement John Carlin describes. But that is why we should be monitoring the US contemporary linguistic scene: to learn from it.
The Cambridge Encyclopedia