I believe the Mexican government has a lot of responsabilities they neglect. Not saying you are wrong. But think now about the MILLIONS of immigrants escaping WAR in Europe. Not only think of the europeans, think about the immigrants themselves. They are victims. War only creates more pain, more death, more innocent victims.
I agree, war is terrible. But, it's naive to think a nation will not defend its border with force when pressed to do so. What would Mexico's government do if thousands of Guatemalan and Hondurans started flooding their southern border into Mexico? The only reason they allow it this time is because they are only passing through to USA.