The great facilitator of crime and corruption in our day is offshore accounts, hidden under the guise of shell corporations. Drug cartels, foreign-aid skimmers, tax avoiders and ill-gotten gainers of all nationalities love them. So do American political manipulators.

Federal investigators are attempting to pry open some offshore accounts for evidence of wrongdoing in high places. If we could routinely monitor these accounts, we would see how the world really works. It would not be pretty, but depriving crooks of hiding places is a necessary step to fighting corruption and poverty and helping economies grow.

As a technique for concealing wealth transfers, such gimmicks are not terribly new. Swiss banks have waxed fat for generations on secret deposits, which included both Nazis and Jews fleeing Nazis. German chemical giant I.G. Farben attempted to hide its assets during World War II under the name “Interhandel” in Switzerland. Didn’t work.

The big jump in secret offshore accounts, however, came with two major postwar changes: growing foreign transactions and small countries such as Cyprus and the Cayman Islands, whose lax banking regulations invite secret accounts, now estimated to top $1 trillion. Panama and Delaware facilitate the establishment of shell corporations, fake entities to conceal true ownership. “Presidential attorney” Michael Cohen has founded many Delaware corporations, including the one that paid Stormy.

Cohen received several million from a variety of interests trying to understand and/or persuade the new Trump administration. This case is separate from Special Counsel Mueller’s Russia probe; its events came after the election. Mueller handed it to the Manhattan U.S. attorney, but if Cohen cracks, he could reveal Russian connections before the election.

One such connection: This March, Russian billionaire Viktor Vekselberg flew in on a private jet and was interrogated by federal agents at the airport. In April, Vekselberg was put on the Magnitsky sanctions list barring him from his U.S. accounts. His Renova firm and its U.S. branch Columbus Nova paid Cohen at least $500,000 for “consultations” (i.e., getting off the sanctions list).

The payers thought they were buying influence, but where did the payments go? Buried offshore under shell names, they will not likely appear on anyone’s tax returns or corporate statements. Suspicious Activity Reports (SARs) required of American banks reveal some of what Cohen received. A Treasury official leaked that a couple of crucial SARs are unavailable, but the banks have their own copies.

Two basic possibilities: (1) Cohen kept all the money or (2) he passed most of it through to Trump entities. The White House, which now shuns Cohen as an insignificant fixer who promoted himself to gullible corporations, favors the first. They will proclaim: “We had no idea about his misrepresentations and got nothing from them.”

Does that make sense? Would Cohen covertly keep the money, thereby inviting Trump’s wrath and/or an IRS audit? It would make more sense to declare the income and pay the tax bill. (Will Cohen amend his 2017 return?) But if he passed the money through — via shell corporations and overseas accounts — can he count on Trump pardoning him? If he doesn’t, Cohen could tell all. I suspect we have here a case of mutual blackmail.

Worst for Cohen would be if money from Russian “investors” like Vekselberg did not reach Trump. Cohen, from his time as a lawyer for the Russian mob in Brighton Beach, knows what happens to those who cross powerful Russians. Cohen, looking increasingly haggard, has aged quickly, as have several other Trump surrogates and supporters. The pressure on them must be incredible.

Eventually, someone will crack and explain where the money ended up. Trump could run afoul of the emoluments clause prohibiting foreign rewards to a president. One dodge would be to proclaim the money went to Trump entities without the president’s knowledge or permission. This would work better if Trump had divested himself of all his enterprises.

Offshore accounts are a major world problem but, alas, protected by national sovereignty, will likely remain untouched. Americans must list any foreign bank accounts on their income-tax forms. But accounts of overseas shell corporations may remain hidden from the IRS.

The big weakness of offshore accounts is lack of any guarantee that depositors will get their money back. Are these overseas banks scrupulously honest? Do these island governments offer legal protections or deposit insurance for foreign investors? Could overseas bankers skim accounts and lose billions in crooked loans? The smart operators who think overseas accounts are clever and safe could see them vanish.

Washington should require transparency for all transactions with offshore banks, including the principals’ real names. Those who haven’t registered their accounts will not be able to repatriate their money. Such laws with teeth are improbable. Too many powerful interests benefit from secret offshore accounts. All these tense conflicts will make a great TV series, a mashup of “Billions,” “Homeland” and “The Americans.”