I noticed.
Newtonian physics gets in the way of maneuverability in re-entry vehicles. The “typical” ICBM or SLBM travels between 18 and 30 times the speed of sound. That’s travelling quite a few meters in a millisecond. The inputs required to move a warhead from a purely ballistic path at those speeds is tremendous... The hardware required would be far heavier than the warhead itself. The computational speeds that would make even minor course corrections would, as every other system, suffer from some instruction and communication latency. Even latencies in the sub-nanosecond range would result in what we in the missile business used to refer to as a “miss”.
Cheaper and more effective to field more warheads.
As to “cruise” type missiles, going exoatmospheric is largely unnecessary and sacrifices range to no great gain.
Much slower, even in their hypersonic configuration, they may be amenable to maneuvering, but this renders their flight time longer, again putting the warhead at greater risk.
The idea of a maneuverable re-entry vehicle is solid handwavium.