in any case, 5th gen warfare is warfare using the previous 4 iterations methods, tactics and strategy but equally "not having a war" - 

so the use of non-state actors (ISIS, Hamas, EDL, IRA, Proudboys, BLM, Azov, Wagner) to wage war on behalf of state actors. 

The reason is nukes. it's just not possible to have a hot war between the countries because nuclear escalation is pretty quick so becomes a null state of play. 

So the only way to keep the game going is to keep playing, all the time, on every sphere - land, sea, air, space, digital and psychological. In fact, you'll always feel like WW3 is about to break out, though it never really will (hot war) and that anxiety will be on-going until nukes are removed from the equation or the world is a radioactive wasteland.