Each new weapon or technological development simply changes the means of combat, but so long as we are humans, and driven by things like fear, anger, duty or seeking glory, then humans will discover ways to carry on fighting. Humans still fight wars, and even conventional wars despite may of the combatants being armed with nuclear weapons.
The idea that an Alcubierre warp drive releases a massive radiation "pulse" when the drive bubble is collapsed is interesting, but it simply places new constraints and restraints on both the individual ship Captains and the organizations controlling the ships.
For Captains, they will need a very accurate plot of where their compatriots are going to be in space, to avoid "frying" their own ships in "Blue on Blue" events. Given the radiation pulse is thought to have a range of one light second, it suggests that the tactics in a squadron or flotilla will need to take light second spacing into account when planning manoeuvres. This immediately makes many traditional ideas of fleet manoeuvre and battle obsolete: one light second is almost the distance from the Earth to the Moon. Mutual support between ships will be exceedingly difficult, and ships themselves may have to become quite massive to both fight individually (since support os a light second away), and also to house weapons that can be effective against targets a light second away (anyone who was closer when you exited warp is already a casualty).
The Atomic Rockets "Conventional Weapons" page outlines a laser weapon which fits the bill, but the Ravening Beam of Death (RBoD) is a Free Electron Laser driven by an electron beam accelerator a kilometre in diameter, which gives you an idea of the size of the ship
Ravening Beam of Death
At 1 light second, therefore, the beam is depositing 2E12 W/cm3 in iron at the surface and 7E11 W/cm3 at 0.25 cm depth; 1.2E11 W/cm3 in graphite at the surface and 5E10 W/cm3 at 4 cm depth; and 2E11 W/cm3 in glass at the surface and 7E10 W/cm3 at 2.5 cm depth. Using 6E4 J/cm3 to vaporize iron initially at 300 K, we find that iron flashes to vapor within a microsecond to a depth of 0.9 cm. The glass, assumed to take 4.5E4 J/cm3 to vaporize (roughly appropriate for quartz) will flash to vapor within a microsecond to a depth of 4 cm within a microsecond. Graphite, at 1E5 J/cm3 for vaporization, will flash to vapor to a depth of 0.7 cm within a microsecond (the laser performs better if we let it dwell on graphite for a bit longer, we get a vaporization depth of 10 cm after ten microseconds).
So instead of close combat or exciting dogfights between ships, we have massive arsenal ships mounting gigantic laser weapons. The ships are dispersed in an "open" grid over an imaginary sphere, separated by a minimum of one light seconds distance. The enemy is also widely dispersed, to avoid being fried by the energetic release of photons when the invading fleet arrives, and so are similarly sized and equipped, capable and indeed having to fight on their own, at extreme ranges, in order to prevent themselves from being fried by the energetic radiation of their own or the enemy fleet's Alcubierre drives.
Ships arrayed o this grid would be a minimum of 300,000Km apart
Fleet tactics and strategy will be driven by these extreme ranges, and ship design will emphasize the ability of ships to fight without any form of close support, trusting other ships in the grid to prevent enemy ships from gaining the position to do a flank shot.