I choose to take that joke in the context that it's a jab at illegal immigration. You can't say anything in this country anymore without being decried as a racist.
Personally, I would be willing to pay hard-earned cash to see an end to all of these illegal squatters who are destroying our economy. Send 'em ALL back from whence they came. Mexicans, Russians, Koreans, WHOMEVER!. If you are in this country illegally, GET OUT. It's not a matter of race, it's a matter of homeland security.