In the U.S. we have SSNs (social security numbers) and driver's licences. India is rolling out a 21st century answer to the problem of uniquely identifying its population with technology to minimise the probability of false, duplicate, or un-recoverable identities being created.
The technology gives the Indian government the ability to "track" its citizens no further than the American government can "track" hers through their SSN-linked bank accounts, cell phones, and government office activity. In a nut shell, the technology hashes an individual's iris and fingerprints into an ID, allowing for the ID to be easily verified in a de-centralised manner. In contrast, verifying a U.S. ID requires patching in to a centralised database.
Can an iris scan and fingerprint be faked? Of course. But I'm not sure who's arguing for the security of U.S. identity cards given that a stroll through Greenwich Village will afford me multiple solicitations for fake IDs.
Ignore even the problems of having a democracy where you don't know who your citizens are nor if nor how many times they've voted and think about how difficult it would be for an individual with no verifiable identity to enter into a long-term contract. Would you give him a mortgage? Or a loan to plant his fields? Knowing well that if he doesn't feel like paying you back he can change the name he goes by and you won't know the wiser? On the other side, if you're a government official who knows nobody knows how many people are in your district, wouldn't you feel less comfortable embezzling funds from intended recipients if they had a way of proving they never received their handout?