Immigration to the US is a privilege. Thousands of people spend fortunes and decades to become citizens. Many are forced to return home many times, leaving jobs and friends. They are forced to learn about American history and culture probably more in depth than what is taught in public schools k thru 12. One day they pass their tests and pledge and oath to this country.
Illegals hop a fence and hide underground for years taking jobs from poor or uneducated Americans and do so at a cheaper pay because they don't plan on staying forever. They don't aspire to be American, just richer than their counterparts in Mexico and at the expense of uneducated and poor Americans.
Illegals at one time didn't know how to milk the system of free lunches and welfare designed to help poor Americans, now its a draw for coming here.
If Canadians were the illegals, and I assume you mean white Canadians, the liberals would object because they are white and Conservatives would object for the same reasons stated above. I know how many thousands Canadians have to pay just to work here. Do you think they should forget all that American immigration law junk and follow the lead of the Mexicans? If so where do you or liberals draw the line? Haitians? English? Iranians? Why do liberals choose specifically Mexicans to be the ones to be able to flaunt immigration law?
Possibly because the Mexican population is one of the biggest minorities in the country and the main immigration complaints are against the Mexican-American population