So, when you mention that Kennedy And Bush did somthing in regard to visas back in 1990, I don't know what you are talking about because visa is a word that means different things depending on how it is used. It may be germaine, but I think it is better to discuss the issue at hand.
For example:
A compromise bill would allow X number of workers in on temporary work visas. It would also establish a plateau/method that allows previously temporary work visa holders to acquire permenant visas. It also establishes quotas.
In contrast, Bush/Cornyn would allow X number of workers in on temporary work visas and no-one gets a permenant visa. It also establishes quotas.
All temp work visas have quotas that can be changed depending the need. Tech worker visas were lowered during the recession and will be soon be raised as the economy expands. When the ag worker visa and non-ag worker visa get reformed, they too will be adjustable to needs.
We have had these ag and non-ag visas for many, many years. As Bush said, they are broken and need to be fixed. No doubt they worked well in the beginning but the dems snarled them up to benefit the unions. Had these work visas been allowed to change thru time to satisfy our need of guest workers, there would be very few illegals here.
Well that was the argument the mass immigrationists gave back then, more legal visas would cut down on illegal entries. Kennedy's mind wasn't on the Mexicans so much but rather the illegal Irish population. Regardless illegal immigration exploded despite what was claimed would happen.
There's also a history of guest worker programs for Mexicans dating back to the 1940s and 50s. During that period millions entered illegally despite the legal opportunities. It wasn't until Eisenhower and Congress put their foot down and actually enforced the law that it stopped.
History has proven time and again it's wishful thinking to believe guest worker programs or increased visas will stop the invasion. Only enforcement of the law does that, something which hasn't occurred in the last 15 years.