You can always tell when your policies have failed. You point to the validation of like-minded posters on a message board, rather than their results.
Look just to be clear, I am not saying that your model and your preferred policy action is incorrect, I am saying that you are asserting certainty when it is not warranted. Maybe all of these things are connected, but maybe they are not, the data are inconclusive, at least the data you've provided here to support your position. Believing, with unwarranted certainty, that you your model is the true and only model leads to political impasse and gridlock, it's like Muslims and Catholics trying to work together to plan a Hanuka feast. If we can't even agree on the mechanisms that drive the system then how can we predict the consequences of policy solutions. Uncertainty is a fact of life and it ok to implement policy solutions even though we don't have the one true system model all worked out. You'll make far more headway, towards actually useful solutions, if you accept uncertainty and keep an open mind on what might work.