It's both harder and simpler than it sounds.

In PA, the Dept of Transportation requires the same proofs of ID for a driver's license as for a state ID card, the photo ID for non-drivers. Yet PennDOT's state ID card is not sufficient proof of identity for the US Dept of State to issue a passport, though a PA driver's license (with all the same proofs and procedures) is. State has said this is because some states' photo ID cards for non-drivers are so easy to forge it's laughable, so they have eliminated the entire class of documents as a proof of ID.

To get a driver's license, you have to be able to present two documents that prove who you are, like a birth certificate and a birth announcement cut from the newspaper. These same documents suffice to get a Social Security card for an infant. Yet if you need another copy of your birth certificate, you need to present your driver's license (and $10.00).

School report cards are also considered proof of existance by government, but a child must have a birth certificate and a Social Security number (obtained with the birth certificate) in order to be enrolled in school.

So many of these documents are circularly referential that it's scary. If you lose a certain number of them, or if you're a naturalized citizen and lose your naturalization certificate (a unique and unreproducible document) through disaster, you have no way of proving your identity except through sworn statements of people who know you who themselves have proper documentation.

Usually, the only document that has an address on it along with a picture is a driver's license/state ID card. (Military IDs are acceptable for a lot of government activities, but I don't think they list the holder's address.)

Citizenship and residence are very important to establish when talking about voting. If person is to be identified as a citizen and a resident, a photo is required. Driver's licenses can be issued to non-citizens in many states, but non-citizens can't vote. So it's obvious to me that what is required is a uniform national ID card, if that's where you want to go with this. Not the driver's license, which can be issued to non-citizens, and which can only be held by people competent to drive (not the same group as those eligible to vote). There's already too much variety in the application and execution process for IDs issued by individual states, as the Dept of State's problem with accepting the individual state photo IDs illustrates.

If it's required to have such a card by the government to exercise one's franchise, it must be free for everyone. No ifs, ands or buts. People must not have to pay to vote. Voting rights are not a fundraiser. The effort that it will take a person to show up with the proper documents or witnesses and get the freaking card ought to be enough effort for anyone to show they "deserve" to vote.

If states want to continue to issue state ID cards for non-drivers, that's fine. Driver's licenses can cost whatever the state wants, and can continue to be under the jurisdiction of the state in question.

We can have another whole level of bureaucracy to shadow and complement the Dept of State's international passport services, administered by the Dept of Homeland Security. We can call them "internal passports". How about that?