Those conditions existed from prior to the 1960s to 1986.
During that period of time about 35,000 people came across our border illegally each year.
What changed?
During the 60s, 70s, and early 80s, we picked up illegals and deported them.
In the late 1980s, we stopped doing that. Our officials refused to enforce our borders and immigration laws. And we had some great laws.
1. Employers were on the chopping block if they hired illegals
2. Penalties for coming across the border were strengthened.
3. More border agents were added.
Well that was great, but nobody enforced the law.
Then Bush started mouthing off about amnesty, and all of a sudden we had between 2 and 3 million people coming across our border every year.
During this time our laws concerning illegal immigration went from the sane thing to do, to the most racist thing in North American history. And our leaders allowed the matter to be gamed like this. No matter what they Left, Mexican nationals, Mexican supporting activist groups, or the Mexican government said, it was crickets in response.
If we enforced the laws on our books uniformly, the illegals would go home, they would stay home, and our problems would be over.
People don’t break in when they can’t work, they don’t get freebies, they get busted, they cause trouble for their family already here, and they get no benefit whatsoever for having done so.
Plyler v. Doe, 457 U.S. 202 (1982), was a case in which the Supreme Court of the United States struck down a state statute denying funding for education to children who were illegal immigrants and simultaneously struck down a municipal school district's attempt to charge illegal immigrants an annual $1,000 tuition fee for each undocumented student to compensate for the lost state funding[1]. The Court found that where states limit the rights afforded to people (specifically children) based on their status as aliens, this limitation must be examined under an intermediate scrutiny standard to determine whether it furthers a substantial goal of the State.
http://en.wikipedia.org/wiki/Plyler_v._Doe
as well as increased funding for all welfare benefits.
the reason that people didn't come emmass before 1980 was also economic. the Reagan economic reforms created a massive economic boom in this country making those in Latin America have more of an economic incentive to risk the border.
On top of that the Federal government starting giving huge amount of welfare to illegals again making the incentive to cross the border.
Like I said you can enforce all you want but if you do not change the incentives people will find a way to get here.