Al Franken sounds worried.

“The Post Office is in the Constitution,” the Minnesota senator recently reminded a St. Cloud Times reporter. “It’s been around since the beginning of our country. … We all have to remember our values.”

After a U.S. Postal Service announcement that financial woes may force it to discontinue Saturday delivery—a measure backed by President Obama—members of Congress are scrambling against a May 15 deadline to reassure constituents that no, they won’t stop receiving their Lane Bryant catalogs and carpet cleaning circulars over the weekend. Meanwhile, a bipartisan coalition including Sens. Tom Carper and Sherrod Brown is pushing for these and other cuts to be allowed to take place.

A sign of these austere times? Not so fast: The Postal Service also threatened to cut Saturday service in 1947. Oh, and in 1957. And 1968 … and 1975 … and 1987 … and 2001.

Nearly every decade seems doomed to suffer a standoff between Congress and the Postal Service in which Saturday delivery is the hostage. Congress is generally the first to blink: When Saturday delivery actually was discontinued for a single day on April 13, 1957, it was only because extra funding wasn’t approved in time for the postmaster general to revoke his order. (It probably didn’t help when one congressman scoffed that his threat was “an unadulterated bluff.”) The chair of the House’s post office subcommittee, facing yet another threatened mail-free Saturday in 1975, was not much more appreciative about what he termed “reprehensible scare tactics.” Summoning the postmaster general, he scolded, “For years, Mr. Bailar, you and your predecessors have threatened labor cutbacks and delivery curtailments every time you want more money.”

Will this time be different? First-Class Mail usage peaked in 2001, and since then ballooning pension costs and the incursion of email have pushed the USPS into what looks like a death spiral. A 2010 Government Accountability Office report (pdf) forecasts $238 billion in losses this decade, with the loss rate hitting a staggering $33 billion a year by 2020. Even the elderly and rural constituencies traditionally invoked by the National Association of Letter Carriers during budget battles might not be able to convince Congress to live with those kinds of numbers.

The NALC is not exactly a shrinking violet: Back in 1950, after an era of up to four residential deliveries a day, they denounced the switch to once-a-day mail as “a rape of the postal service.” Now crusading against budget-driven Saturday cutbacks, they allege the existence of a $75 billion pension overpayment to the Treasury by the Postal Service. Alas, separate analyses in 2011 by the GAO (pdf) and the Office of the Inspector General (pdf) into a Saturday-saving windfall found it to be mere wishful thinking.

But would five-day mail be so bad? Countries ranging from Canada and Australia to Finland and Singapore have already had it for years—decades, in some cases. (The diminutive Channel Island of Guernsey became the latest postal system to switch last month.) Economists in these countries who have studied postal systems hardly seem concerned about five-day delivery.

“I’ve assumed that postal services are weekday, the same as lots of banks, insurance companies, and so on,” emails John Quiggin, a professor of economics at the University of Queensland. “It’s certainly not a topic that ever comes up, even among people who’ve lived in the U.S.”

An intriguing 2011 GAO study of foreign postal systems (pdf) not only noted the use of five-day delivery overseas, but also such innovations as a pilot project in the Finnish village of Antilla. Mail there was delivered just two days a week; on other days, text messages notified villagers of any letters sitting at the post office. They could then either pick them up or simply wait for the next biweekly drop-off.

The future may look like Antilla—because going to five-day delivery won’t even begin to address the USPS’s woes. A 2011 Postal Regulatory Commission study (pdf) indicates many of the alleged savings of five-day delivery are illusory—that, as all the political bluster suggests, cutting Saturday mail is a better bargaining chip than it is an actual budget measure. Rather than saving $3.1 billion yearly, and within a year’s time, as the USPS claims, the PRC estimates a yearly savings of $1.9 billion, and only after three years. Both figures are a drop in the bucket compared with the kind of losses the USPS now faces.

So a measure that Canada adopted back in 1969, it turns out, might not help the United States much in 2012. And to Ian Lee, an assistant professor of business at Carleton University, the USPS and his native Canada Post now face problems that strike at the very idea of postal systems themselves.

“The post office’s public utility is diminishing because the public doesn’t use it,” he says. It wasn’t always that way. Working at a Canadian bank in the 1970s, he saw the country reel from the effects of postal strikes: “It was apocalyptic. Banks were absolutely dependent on the postal system.”

During a 2011 Canada Post strike, by contrast, few people took much notice of the interruption. It’s a sign that postal systems, professor Lee warns, “are in a long, terminal decline.”

Congress isn’t likely to save this patient. Postal unions are large, vocal, and solidly Democratic; attempts to break up or reduce the Postal Service are primarily Republican. Even well-intentioned reforms—and not all are—will be viewed with suspicion by congressional Democrats. Their worries aren’t purely political; the post office’s historical importance as a minority employer means that closings and layoffs, if not accompanied by serious retraining and educational opportunities, could prove devastating to black communities.

The Postal Service’s overcapacity in labor and facilities recalls nothing so much as the politically explosive issue of demobilizing redundant military bases at the end of the Cold War. Indeed, the GAO has already made the connection, with an idea that has received little coverage: “Congress,” they report, “could set up a mechanism, such as one similar to the Military Base Realignment and Closure Commission.” The BRAC process hands closures to a panel appointed by the president; for its recommendations to take effect, Congress need only remain silent, rather than cast politically ruinous votes. If that model allows congressional Republicans and Democrats alike to walk away from what would likely follow, postal workers may have a lot more free time on their hands, and not just on Saturdays.