Are you freaking serious? That's double the current population. Growth like that in such a short amount of time is not sustainable in the slightest.
Not to mention with the current attitudes towards immigration you're just asking for civil rebelliousness to go haywire.
Why do you think so, when all what it seems is not. America, assuming it takes in 800 million immigrants that leech off 649$ each year (though usually the opposite happens), the average native income would lower from 54,370 $ to 52,760 $. That's naught. The population density for each farmland would grow from 179 to 623, about as much as Austria (598) or Portugal (665), far less than some countries like Japan and Hanguk.