From Bill Gertz in the Washington Times comes "Chechen terrorists probed":

U.S. security officials are investigating a recent intelligence report that a group of 25 Chechen terrorists illegally entered the United States from Mexico in July.
The Chechen group is suspected of having links to Islamist terrorists seeking to separate the southern enclave of Chechnya from Russia, according to officials familiar with intelligence reports.
Members of the group, said to be wearing backpacks, secretly traveled to northern Mexico and crossed into a mountainous part of Arizona that is difficult for U.S. border security agents to monitor, said officials speaking on the condition of anonymity.

The intelligence report was supplied to the U.S. government in late August or early September and was based on information from an intelligence source that has been proved reliable in other instances, one official said.
A second U.S. official said the report is being investigated, but said it could not be determined whether the group of Chechens actually entered the country, as the intelligence source reported.
"We don't know whether or not that report is true," this official said.
A spokesman for U.S. Customs and Border Protection confirmed that the intelligence report was provided by another government agency, but said Border Patrol agents were unable to verify its accuracy...

Up to three million people will cross our southern border this year.

If only a few people were crossing, groups like that above would stand out. But, we aren't ever going to be able to reduce the flow that sharply. However, we could reduce it as much as possible in order to make the job of the Border Patrol that much easier and to make those trying to cross stand out as much as possible.

The way to do that is to start fining those employers who are putting the rest of us at risk and to reduce the other incentives to being here illegally, such as free healthcare and driver's licenses. However, because of Bush and many others that is not being done.

If terrorists do attack the homeland after coming over the border, look through my immigration categories for the companies, groups, and politicians that are to blame.