(Original non-sexy title: "This is How Voter ID Laws Ought to Work")
This should be the federal law regarding voter ID:
(1) Pollworkers should have access to computerized voter registration files.
(2) If the state requires voter photo ID, these files should contain a digital copy of whatever voter photo ID the state requires.
(3) Voters may, but need not, bring their own copy of their photo voter ID.
(4) If the identity of a voter is challenged, refer to the photo on the computer file to verify identity.
(5) If the voter does not have ID, there should be provisions for a poll worker to take a photo of them right then and there with a digital camera and upload it to a database (separate from the vote count) indicating their identity; this will subsequently serve as their voter ID for future elections. There should be no cost for this service and it may be that we'd want a physical card to be mailed to the voter subsequently.
(6) If there is any serious concern about a given voter's identity, maybe the voter could be required to vote by a provisional ballot until their identity is confirmed after the election, but this should not be easy (and perhaps the loser in the challenge pays the cost.)
(7) If a state does not have a copy of the photo voter ID on file, federal law should preclude its ability to deny anyone the ability to vote.
Some extrapolation and analysis below.
Voter ID is absolutely a kind of "poll tax," barred by the 24th Amendment, although its cost is in time and effort as well as in money.
It is absolutely unnecessary to have individual voters procure such an ID before the election or have it with them at the polls. If the state wants to impose the requirement, the state can keep the files online. We have this thing called the Internet now. Thumb drives with photo voter ID for all voters in a precinct could be made available to poll workers as well in the event of an Internet outage.
The argument for voter ID does not sound stupid to voters; even if fraud is rare (or almost unheard of) here, it's theoretically possible. So we don't need to fight it head on. We just have to say that if a state wants to require photo ID of voters, it has to have its own copy of that photo ID on-hand so that voters are not denied the right to vote if they cannot get to a place that issues ID or if their ID is lost or stolen. Otherwise, it's a poll tax.
Congress could pass a law with this requirement this year. If states want to enforce their voter ID laws this year, they had better get cracking and compile those databases. The states can have their laws so long as they accept the (fairly minimal) commensurate burdens.
I think that we'll find, though, that when if and when voter photo ID is no longer a useful way to prevent disfavored people from voting, its proponents may lose interest in demanding it. What would be the point then -- good government or something?
If states wouldn't agree to these sorts of requirements, then their motives are suspect and they should not be able to enforce their voter ID laws. Problem solved.