How is the war playing out in Iran?

Iran stands at a crossroads. With its top leadership assassinated early in the joint US-Israeli offensive, the remaining layers of power have been trying maintain control. There are concerns that after January's mass anti-government demonstrations, this war would lead to chaos. US President Donald Trump has made clear his desire for regime change in Iran. Many argue that what remains of Iranian leadership is struggling for survival. But Iran's leadership is notably complex. It has parallel armies, multiple intelligence services and several command structures So, will it survive? Or is the situation spiralling out of control?