In former times, troops rode horses -making it possible for them to get from A to B as a dispersed group. Attacking them therefore had to be done largely one at a time.
Now that warfare (or ‘peacekeeping’) is mechanised, soldiers get into increasingly large vehicles which need massive amounts of armour to resist eg landmines and rockets.
Today’s invention is a way to protect soldiers from roadside bombs and other weapons directed at large vehicles.
It is the armoured ATV (or four-wheeled motorcycle).
Militaries around the world already use these vehicles and the cost of buying one per soldier on patrol is certainly less than buying the equivalent capacity in armoured Humvees.
By adding a steel shell around the driver of each ATV, it becomes much harder to kill numbers of soldiers, since they are dispersed, still quite fast moving and with some significant individual protection.