Beyond its durable imprint on American civic life, the Watergate scandal of four decades ago left its mark on political language. For one thing, that suffix will not go away. Commit a major folly, and you can count on some headline writer describing it as Whatever-gate. Forty years later, investigations into wrongdoing by public officials still routinely yield the Watergate-era chestnut: What did so-and-so know, and when did he know it? Americans are well aware, too, that they would be wise to “follow the money,” abiding words bequeathed by the shadowy figure Deep Throat in “All the President’s Men,” the 1976 Watergate-themed film.

“Follow the money” was sound advice in the 1970s. It is even more sensible these days, when cash courses through American politics like a flash flood.

“Watergate” was a catchword for a multitude of government and political sins. At its core were secret, and illicit, contributions to the 1972 re-election campaign of President Richard M. Nixon. Some Nixon retainers went to prison. Also, more than a dozen American corporations were found guilty of criminal behavior, typically for having showered barrels of dollars on the campaign in the hope — no, expectation — that their largess would translate into favors from the administration. As can be seen in the latest video documentary from Retro Report, tracing the money side of life from Watergate to today, much has changed. Oh, the cash still flows, and a fair amount of it continues to be secret. But what was deemed ill-gotten loot 40 years ago is now legally accessible, countenanced by no less than the United States Supreme Court. And the money no longer rains down on presidential and congressional campaigns by the barrelful. By the truckload is more like it.

Big political scandals have often inspired laws to address whatever went wrong. Watergate was no exception. The same went for lesser situations that were eyebrow-raising all the same; the trading of campaign contributions for sleepovers in the Clinton White House was one example. With almost every cycle of wrongdoing and attempted reform, Americans have had to absorb a sometimes-bewildering array of political terms, like “soft money” versus “hard money,” or PAC — it stands for political action committee, in case you forgot — versus “super PAC.” They have also had to come to grips with Supreme Court rulings that do not always seem consistent, one with another, on what sort of behavior is kosher.