I have long been a proponent of a guest-worker program between the United States and Mexico, and in particular I have proposed that Arizona would be an ideal location for a pilot project.

But my view is that you need a system at the border. You need some fencing but you need technology. You need boots on the ground. And then you need to have interior enforcement of our nation's immigration laws inside the country. And that means dealing with the employers who still consistently hire illegal labor.

Nonetheless, to the extent that terrorists have come into our country or suspected or known terrorists have entered our country across a border, it's been across the Canadian border. There are real issues there.

Such a system would be very, very expensive and laborious to have, given the kinds of border we have. Scientists and engineers aren't even sure they have the technology to make it work

As part of our layered approach, we have expedited the deployment of new Advanced Imaging Technology (AIT) units to help detect concealed metallic and non-metallic threats on passengers. These machines are now in use at airports nationwide, and the vast majority of travelers say they prefer this technology to alternative screening measures.

The last thing the Department of Homeland Security is about is infringing on anybody's constitutionally protected rights.

It's all about who gets to work and making sure they're legally present in our country. And to do that nationally E-verify becomes a key component. It certainly needs to available, effective and as inexpensive as possible and that employer needs to use it as a tool. Some of the arguments that are made about how it works or does not work don't carry much water with me. I've already used it for several years. It works.