Why? Because said regimes - besides always being bigoted and repressive - always open the door to massive heists by the country's own elites against their own people.
The resulting calamity always then becomes a major foreign policy liability for Washington - and the more closely the U.S. can be tied by its adversaries (mainly China) to said Argentine regimes, the more of a PR burden they become.
As we speak, Milei is pulling all the stops to charm the Biden administration into lending them $15 billion - which they will then use to finance capital flight (leaving everyone else the tab).
Since like all Latin American right-wingers, Milei's people (especially Caputo, the money-laundering Econ minister) see Americans as gullible and easily flattered, they pretty much assume they'll get the money - smiles and all.
But it's worth recalling that the last time Caputo got away with such a swindle (the $45 billion Macri bailout, which Trump coerced the IMF into coughing up), the result was nothing but trouble.
Thanks as always, Judi, for keeping up with the hijinks in Argentina - and elsewhere.