The power point presentation of Bob Johnson's talk at the AGM has provoked a couple of responses. One of them is a link to www.sciencealert.com/boeing-has-patented-a-plasma-force-field-to-protect… … in order to protect army vehicles and the like rather than satellites in the sky. The heat creates a plasma shield denser than the surrounding air which is able to deflect or absorb energy from an incoming shock wave. Ian Tresman provided a further link, per magnetic fields and plasma – https://en.wikipedia.org/wiki/Magnetic_mirror#Magnetic_bottles
See also www.sciencedirect.com/science/article/pii/S1342937X10001966