How does such a tariff even work? Can't an airline finance all of its aircraft through an entity in the Maldives or whatever?

Airbus had to move production from Quebec to Georgia (US)

It wasn't Airbus yet, so more like: Bombardier had to sale a controlling stake to Airbus to gain access to its Georgia production facilities.

Why, though? I am just wondering how it takes effect. The carriers often lease the planes from special-purpose entities. If such an entity is based in Liberia, where does the tariff apply?

Alabama not GA