There really is no argument. Mexico built their southern border wall to keep out illegal immigrants from South America. The US is doing the exact same thing only difference is, is that trump will be doing it and that makes mexicans mad. Boo hoo. It's 100% hypocrisy by the Mexican people to have that stance. Seems like they are mad that their free ride will be coming to an end. Mexico it's time you joined the rest of the world and pay your dues to get in like everyone else. Your not special. Merit based immigration also needs to happen in america! Other countries do this with amazing success so why don't we?
It is very hypocritical of Mexico to propose a construction wall along its Southern border, while they were against Trump's suggestion of building a wall along the Mexican border with US to keep of Mexican immigrants. Mexican president claim that the Southern border will keep off immigrants from Guatemala, Honduras and Salvador from reaching US is in bad faith and very hypocritical in all aspects.
Mexico's talk of a Southern Border Wall Plan is reactionary behavior and is quite honestly to be expected when US politicians have simultaneously overtaken the Mexican economy and been unsupportive of freedom of movement. To fault Mexicans for heading further north for opportunities lost at home seems like the real hypocrisy in the situation.
No, it is not hypocritical of Mexico because they are simply responding to Trump's remarks. They are showing that they will not back down from bullying. They are asserting their rights as a nation and should be praised for doing so. Trump is ruining relations between nations and should be punished for it.
Without knowing what kind of immigration issues Mexico is facing, I can't say if its plan to build a wall is hypocritical or not. It sounds like the intent is to keep out Salvadorans and Guatamalans fleeing violence, and that one issue is folks passing through on the way to the US. I don't know what kids of numbers they're getting or how disruptive it is.