The quiet Pakistan general waging war against Imran Khan

[S.Y.A]

Yes, IK did something illegal when he asked the then COAS to get rid of the DG ISI. That's called interfering within the military ranks. PM can only select the COAS.

When Nawaz Sharif (Allah jannat naseeb karay) sacked the COAS Gen. Pervaiz Musharraf, he had the legal right to do so.

isi reports to the PM, not the COAS. the PM appoints ISI dg, not the COAS. its the COAS that has usually interfered with PM's authority. A PM is well within his rights and authority to remove or demand removal of isi DG, whether its nawaz, ik or zardari.