The Iran nuclear deals seems to have represented a fundamental strategic choice which the Obama administration made and which Trump has now rejected without either really explaining why.
The lack of public debate is reflected in the non-ratification of Obama’s Iranian nuclear deal and the lack of Congressional consensus behind Trump’s actions toward Iran.
Maybe this is because both the Dems and Republicans don’t want to draw attention to the withdrawal from Iraq or entering Iraq in the first place, which seems to have destabilized the Arabs and given Iran and Turkey their big chance.
Tehran is virtually certain that Trump will not — indeed politically cannot — return to the Middle East in force and that the Arabs are presently too scattered to oppose them. At the same time Iran must see Israel benefiting from the same Arab weakness.
This, plus the growing realization that by using hybrid warfare Trump need not return to MENA is probably driving a sense of urgency among the Ayatollahs, who must move now lest the tides turn against them.
In this context the Iran nuclear deal, which was supported by Europe and Obama, can be seen as a strategic attempt to buy off Tehran, thereby forestalling more refugees, a course of action deemed more realistic and cheaper than trying to stop them.
Sending the pallets of cash was seen as more economical than gearing up to stop the Army of the Guardians.