Make a reservation at a hotel – by telephone or online – and someone has your credit card number. Write a personal check at the corner convenience store, and you’re asked to show your driver’s license and the cashier writes down its number. Donate money to a political candidate, and the federal government records it and makes that information available in its publicly searchable database. Use a cell phone or Blackberry, or subscribe to OnStar? Your movements are being tracked. Show a Shaw’s card when you buy groceries? The food chain notes that you prefer Wheaties over Corn Flakes, and offers a coupon for them the next time you shop. Rent a horror film through Netflix, or buy a romance novel from Amazon, and the company Web sites cheerfully suggest something else from that genre.

Clearly, there’s a wealth of personal information about us being typed, swiped, scrawled and scanned as we spend our way through the world. And that’s not even mentioning the dozens of times we’re recorded by cameras at gas stations, traffic lights and stores such as Wal-Mart. It’s all a bit disconcerting, given how Americans cherish their privacy.

And given the Bush administration’s proclivity for using that information to thwart would-be terrorists – peeking at library use, sifting e-mails for key words, examining telephone records – it seems that worrying about this is more justified than paranoid.

The flap over the federal government’s Real ID initiative and the last-minute extension granted to Maine to comply with the act raises questions about the government gathering our personal information, as well as about the objections to this practice.

Shenna Bellows, executive director of the Maine Civil Liberties Union, notes that national ID cards have been used by tyrannical regimes such as those in Nazi Germany to oppress “undesirables.” Creating the infrastructure where uploaded scans of birth certificates and other information can be hacked – the recent Hannaford breach comes to mind – is a good reason to avoid such centralization, she argues. The revelation that low-level State Department workers perused Sen. Barack Obama’s passport data is another example of potential abuse. A national ID database could provide “one-stop shopping” for hackers.

At a recent meeting of the Maine Association of Former Foreign Intelligence Officers, Ms. Bellows was told in that world, security is assured through the compartmentalization of information, not centralization. In the intelligence world, information is on a “need to know basis.”

With the amount of personal information we willingly give up, resisting the use of a national ID card, or at least a driver’s license tied to residency proof, seems somewhat misplaced. But Ms. Bellows argues there is an important difference between financial information being at risk – the theft of which could ruin one’s credit – and data a corrupt government could use to harass or even restrain dissidents.

The federal government muddied the waters by asserting Real ID was an anti-terrorism measure, and then suggesting it had more to do with illegal immigration. To win public support for Real ID, the feds must offer some real scenarios in which a new database would make us safer.

When the new president takes office next year, he or she should initiate a national discussion on the boundaries of our financial and political privacy. If we can agree on values, perhaps we can agree on policy.