The fact that Social Security numbers have evolved into a key personal identity tool is purely an accident of history. So it should come as no surprise that their security is highly questionable. A motivated thief can easily find SSNs on everything from military IDs and driver's licenses to tax returns, medical records and utility bills. In 2010 alone, more than 8 million Americans suffered identity theft.
The alternatives are identity proofing systems that bring together data from tens of thousands of disparate sources. By having instant access to this multifaceted view of an individual, you can make connections 99 percent of the time between an individual and their data. Which seems a lot more secure than overexposed and under protected Social Security numbers.