Yesterday, I posted some thoughts on counter-terrorism strategy that charted a different vision from the one laid out by John Brennan last week.  Today, I will be discussing some domestic steps – homeland security measures – that would also provide better security than current measures.

We have already taken significant steps to ensure that relevant information is shared more easily across the federal government and between the federal government and state and local governments.  We have also taken steps to bring the Foreign Intelligence Surveillance Act and other domestic surveillance systems into the modern era.  There is still work to be done on these issues — particularly in order to ensure greater transparency and mitigate the risk of abuse — but on the whole we have moved in the right direction.

As a consequence, my recommendations looking forward focus primarily on three measures that require more work:  Border security, identity assurance, and aggressive red-teaming.

The United States, essentially, does not have control over its borders.  Literally millions of undocumented individuals cross our border annually.  We are largely incapable of tracking even legal visitors and tens of thousands drop off the radar every year.  This is an intolerable situation.  The answer is not to shut down our borders — our nation gains too much from immigrants and foreign visitors — but we do need to be able to control who enters our country, what they do here, and how long they remain.

Allowing more legal immigration would reduce the pressure on our southern border and we ought to consider some sort of “guest worker” program as well.  But if it takes a wall to control the border, we will need to build a wall.  A “tall fence with wide gates” model is likely a requirement for effective border control.  In addition, the United States need to devote more resources to overseas consular functions and building a link-back system to immigration “case officers” back home.  The probation officer model has a negative connotation, but we need to establish in the bureaucracy an office that is responsible for tracking legal visitors and ensuring they do not abuse their privileges.  An individual who overstays his or her student visa has to count against someone.  It can’t just fall into a black hole where no one is responsible.

Second, the United States needs to take identity assurance seriously.  In Iraq, soldiers manning checkpoints are equipped with biometric sensors which link back into databases of suspected insurgents.  At home we still rely on terrorim “watch lists” to check who flies on airplanes.  The United States needs to issue — to all individuals — biometrically-validated national identification cards.  Ideally, these cards would be RFID enabled and sensitive locations enabled with tracking sensors.

With proper safeguards, this approach would not only dramatically increase security but also have significant economic benefits.  It would make identity theft much more difficult, allow for the implementation of unobtrusive micropayment schemes for a variety of functions, and reduce street crime significantly.

Third, aggressive red-teaming short be a cornerstone of domestic counter-terrorism efforts. P It is notable how unimaginative successful terrorist plots have been.  For example, the use of airplanes as weapons had been predicted in advance, and the 9/11 attacks could have been foiled by simply locking cockpit doors and training pilots to never surrender the airplane.  But my impressionistic assessment is that we’ve tended to adopt security measures reactively in response to discovered plots rather than proactively in response to an independent assessment of vulnerabilities.

As a practical matter, there are clearly limits as to how much security is achievable in an open society.  But border controls, a biometric identity assurance scheme, and structuring security measures to independently determined threats rather than in response to often unrealistic “plots” would like provide some increment of additional security at home.

Dr. Bernard I. Finel, an Atlantic Council contributing editor, is a senior fellow at the American Security Project.  This article was originally published at ASP’s Flash Point blog.