Other countries do this too. Expat Iraqis voted in their country's last election. I believe some other countries do it as well.
Those Iraqis (mostly Kurds) are here on refugee and legal immigrant status. This is about a foreign government granting voting status to 5 million plus of it's citizens who are residing in our country illegally.
Not only does this salt the wound of our enforcement efforts, it purposely perpetuates the idea that former Mexicans who are now US citizens and legal immigrants on track to become Americans are still tied to their former country.
The country that made their life so hellish that they had to flee arrogantly dictates that they still owe Mexico more loyalty than this nation that granted them refuge and opportunity.
And some people wonder why I'm so down on Mexico.