"Europe was just as much a mess back then as the Latin American countries are now. Don't forget that the Europeans started the two worse wars in human history. Nazism, communism, fascism, all these 'achievements' came out of Europe. 21st century Latin America looks good by comparison."
Yes, European countries and the U. S. have engaged in wars, just as have Hispanic countries, and have chosen foolish forms of government at times, as have Latinos. However, it cannot be denied that Latin American countries have lagged behind western (Europe and America) for decades in terms of economic development and political stability. It's not a difference in degree, but in kind. Travel in some of the Central American countries (from whence we are getting most of our huddled masses these days) if you want to see it up close (or go across town and see the local colonia). You may want Central America in your back yard; I do not, nor do the polls indicate that the vast majority of Americans do.
Most of our "huddled masses" have come from poor and/or politically unstable countries, whether it be Europe in the past or Latin America in the present. People who live in stable wealthy countries do not emigrate en masse.
I do not want South America as my backyard either, but the hispanics of today are not intrinsically worse than the Europeans of yesterday. Both sets of people came from politically backwards and economically tenuous lands.