Mr. Manafort’s indictment is a case study in international corruption. For years, the indictment says, he operated as an unregistered lobbyist for authoritarian governments, a popular racket in Washington. To avoid taxes, according to the indictment, he set up offshore bank accounts and laundered money through real estate and luxury goods — a common practice that enriches plutocrats while exacerbating housing crises in cities like New York and London by pumping billions of dollars of looted wealth into a tight real estate market.

While Mr. Manafort crossed lines (he has confessed to making false statements and material omissions) and now faces legal consequences, his long career typifies the amorality, opulence and lack of accountability that successive American governments have enabled.

Many establishment Democrats and Republicans in the self-proclaimed “resistance” to Mr. Trump say they are deeply concerned about the Russia scandal, but they have largely failed to consider its full implications.

To “Never Trump” conservatives, the main takeaways are that the United States needs to step up its confrontation with Russia in Ukraine, Syria and elsewhere, and that the Obama administration was insufficiently tough on Mr. Putin. Many Democrats, meanwhile, argue that Russian interference means that Mr. Trump’s presidency is illegitimate and that Mrs. Clinton is not to blame for her loss.

But Russian meddling in American politics is, in fact, the product of a long series of bipartisan policy failures. Democrats and Republicans alike supported trade policies that facilitated the rise of plundered fortunes in countries like Russia and China. For instance, in the 1990s, both the Bush and Clinton administrations encouraged the aggressive privatization of the Russian economy, which resulted in collapsing living standards, a new class of robber barons and a backlash against liberal democracy that Mr. Putin exploits to this day.

Left-wing critics of American foreign policy correctly point out that Russia is a convenient punching bag for hawkish pundits and politicians. But the most powerful counterweights to these hawks aren’t exactly progressive champions either: American corporations have lobbied against recognizing Mr. Putin’s human rights abuses and have sought to exploit Russia’s natural resources. Energy companies like Exxon Mobil, whose former chief executive, Rex Tillerson, now serves as secretary of state, have partnered with Russia and have sought waivers from international sanctions to drill for oil in Russia. A new Cold War would be dangerous, but so would a warmer United States-Russia relationship that enriches oil company executives in both countries.

As a rising generation of leftists increasingly asserts itself within the Democratic Party — and may, eventually, have the opportunity to shape foreign policy — it must articulate a new approach to Russia consistent with its core values. This approach should be driven neither by the interests of the national security state nor by the energy sector. Instead, it should aim to block Russia’s kleptocratic elite from safeguarding its assets in the United States, to clean up the influence of foreign lobbying on Washington and to shut down tax havens for billionaires everywhere. The investigation into the Trump campaign’s Russia ties provides an opportunity to focus on these issues.

“Inequality, corruption, oligarchy and authoritarianism are inseparable,” Mr. Sanders said in a recent address. “Around the world we have witnessed the rise of demagogues who once in power use their positions to loot the state of its resources. These kleptocrats, like Putin in Russia, use divisiveness and abuse as a tool for enriching themselves and those loyal to them.” For Americans who broadly share Mr. Sanders’s views, this should be the real lesson of the Russia scandal.