But if I understand correctly people donate when they don't have to pay tax.

From the twitter posts:

> Individuals who fall just below the threshold one year due the chance price of silver suddenly avoid a 2.5% gvt tax. Those people then increase their private donations to charity (since they have more disposable income + islam calls for alms-giving).

Or in clearer terms:

> ↑silver price → ↑tax threshold → ↓taxes → ↑charity → ↑terrorist financing → ↑terrorist attacks!