One big problem is that Persians and Afghans look a lot like Mexicans. I knew of some Afghans who found themselves stuck in Juarez for a few days and the Mexicans there assumed they were Mexican. They were surprised when they didn’t understand Spanish.
I knew an Iranian woman in San Diego a long time ago. She told me that Mexican people were constantly coming up to her and speaking to her in Spanish because she looked like a Mexican. If those Iranian terrorists dress like a poor Mexicans wearing clothes from the swap meet in Mexicali they will be able to blend in with the hordes of Mexicans over running our border.
To a discerning eye
Afghans and Persians do not look like Mexicans
Tannish skin is the only commonality
Arabs on the other hand do look like Latinos
For a reason
Shared DNA via Sultan conquests of Southern Europe