No, we don't.
One out of seven people in the country today, are foreign born. That is the highest percentage in our nation's history. The numbers are so great, that they're overwhelming our ability to absorb and assimilate them into our culture. It's cultural destruction by inundation.
America actually needs to halt ALL immigration for at least a quarter century, to give us time to assimilate these people. A half century would be even better.
The key to assimilation is not having too many immigrants from any one foreign nation/culture coming in at any one time. Otherwise, they tend to aggregate into ethnic ghetto enclaves that prevent not only the immigrants themselves but their children and grandchildren from assimilating. This is why much of the US southwest is now basically Mexico in everything but name.
In contrast, if an immigrant and hisimmediate family are the only people of his nationality and language in a town, he'll either assimilate very fast or basically starve to death.