Wouldn't that depend a lot on what and how much were targeted?

Seems a sufficient number of satellites in a particular orbital altitude and inclination would be required to create a self-sustaining cascade.

Even then, the Delta-V of tens to hundreds of m/sec to for violent intercepts seems unlikely to eject debris into different orbital regimes; e.g., it takes nearly 4km/sec Delta-V to move from LEO to Geosynchronous orbit. So, totally Kessler-Syndrome-destroying the LEO orbital range would still leave GEO orbital range available...?

Depending on the density of debris in LEO it might be very difficult to launch through to the higher orbits.