Given the racial dynamics of the issue, it has been in GWB's best interests to kind of hope illegal immigration goes away, or remains less salient a problem until he is out of office. It's very difficult for Bush to be hard on Mexican immigrants without also being as hard on the Canadian border, even though everyone knows the big problem is Mexico. He has seen more and more latino votes going towards the Republicans, and doesn't want to see that drop. He is afraid being a hawk on illegal immigration is going to drain that support.
I'm not going to deny that many business enjoy illegal labor. But again, to think 'big business' is buying this issue is quite humorous.
You don't see John Q. Public's interests being served in decreasing illegal immigration? Are you serious?