Speech competency should be a test for citizenship, but not necessarily a Driver's License. Fluent native language should be a requirement for any country's citizenship.
However, that does not mean you can't work at all in a foreign country.
And seeing as how our country is so road / transportation oriented, if a person can understand road signs and the laws of the road, and more importantly, the repercussions of that, they should be allowed to get a license.
And Viking, please point to the section in the constitution that gives us the right to drive cars. Or even point to the section that even mentions cars...