The false premise in the immigration debate

The entire debate on this summer's immigration debate centered on a false premises set forth by the bills proponents: that it was impossible to enact legislation dealing with border security and interior enforcement of immigration laws without some sort of legalization to the current 12 million or so illegal immigrants present in the country and some sort of guest worker program. Senator Arlen Spector succintly summarizes this view in an op-ed today where he attempts to resurrect the immigration bill:

Certainly the government should implement the provisions it has already
enacted to improve border security and crack down on employers who knowingly
hire illegal immigrants. But the important additions on those subjects contained
in the bill defeated in June will not be enacted without also dealing with the
12 million-plus undocumented immigrants and the guest worker program.

Really? Why is that? There is just no explanation for this statement that has no basis in fact. These are mutually exclusive ideas. Building a border fence, hiring more border patrol agents, conducting more raids on businesses that employ illegal immigrants, and increasing fines on those businesses do not in any way require legalizing the status of existing illegal immigrants or creating a guest worker program. Unfortunately, the addiction many businesses have to cheap labor forces politicians to enact meaningless half-measures and pseudo-amnesty that make a mockery of our existing laws. I have nothing against people trying to make a better life for themselves; I do have a problem with those in power who do nothing to prevent the situation from getting worse.