First, you should all know that it is possible to be a liberal and also to support tight immigration restrictions. The rationale is that we are against urban sprawl and environmental devastation, both of which are made worse as the population grows. Opposing immigration can help protect our environment and reduce sprawl, overcrowding, protects wildlife and forest habitats, etc. Also, immigration causes problems for America's poorest citizens, taking resources away from them, lowering our wages by increasing the labor supply (reducing demand for workers, allowing employers to pay low wages with no benefits). Second, you should know that many of the moderate voters we will be relying on are anti-immigration and do support English as the national language. These are powerful and emotional wedge issues that can sway many voters to support the Republicans.
In the past, I would have supported open immigration, open borders, and bilingual education. But no longer. Why? Because our nation has been literally flooded with tens of millions of immigrants. Our highways are overcrowded. Our forests are shrinking. Our resources for education, health, infrastructure are being taxed and eroded because we have to provide services to people who don't have social security numbers and thus don't pay any taxes. But whether you agree with this reasoning or not, if you are practical and if you care about winning elections, you will realize that we will not succeed nationally by supporting open immigration, open borders, and multilingualism. If we want to win, we must restrict immigration to 1 million per year, as mandated by law, and we must tighten our borders. Also, people can still speak any language they bleeping' want to. Making English official language simply forces immigrants to learn to speak English, and there is nothing bad about that at all. And, by the way, this is coming from a long-time liberal progressive who has supported civil rights, women's rights, gay rights, environmental protection, who fiercely opposes American imperialism and wants to see the Bush Administration go down the toilet of history, as it clearly is doing.