The revenue is announced and not collected, because the base can move

The argument

The case against rests first on what is actually collectible. Opponents argue that a tax is not a sum of money but an attempt to take one, and that the attempt succeeds only where the person and the asset can be reached. Very large fortunes are the holdings most able to move: residence can be changed, assets can be held through entities in other jurisdictions, income can be deferred or converted into forms the law treats differently, and the advice required to do all of this is affordable at that level and nowhere else. The mechanism opponents describe is a gap between the announced rate and the realised yield. A higher headline rate applies only to what remains within reach, and opponents argue that the response to raising it is not greater payment but greater avoidance, relocation and restructuring. On this account such taxes raise less than projected while imposing real costs: enforcement effort, litigation, the departure of enterprises along with their owners, and a tax code made more complex by each new rule written to close the previous route. Opponents argue that the burden therefore lands elsewhere. When the projected revenue fails to appear, the shortfall is met from taxes that cannot move, which fall on employment, consumption and property, and opponents argue that these are borne disproportionately by people of ordinary means. The conclusion they draw is not that the wealthy should pay nothing, but that raising their rates further is a policy whose benefits are announced and whose costs are real, and that the honest response is to broaden a base that stays put rather than to chase one that does not.

Premises

Counter-arguments

Proponents reply that mobility is a policy choice rather than a law of nature. Residence based taxation, exit charges, reporting requirements between jurisdictions and agreements on minimum rates all exist precisely to make the base stay put, and coordination of this kind has already narrowed routes once thought unclosable. They add that the argument would license abandoning any tax the wealthy find inconvenient, and that accepting it concedes in advance that enforcement is impossible, which is a prediction about political will rather than a finding about what can be collected.

Rejecting the premises

[Rejecting P1] The reach of a tax is set by law and by cooperation between jurisdictions, both of which can be extended, so mobility is a policy choice rather than a fixed limit. [Rejecting P2] Avoidance responses have repeatedly shrunk where reporting and coordination were introduced, so the behavioural response is not independent of enforcement design. [Rejecting P3] The shortfall falls on ordinary taxpayers only if the shortfall is accepted, which assumes the enforcement failure the premise is meant to prove. [Rejecting C] The premises argue that collection is difficult, which supports improving enforcement rather than declining to levy the tax.