Although the Tasale system is only a short interstellar distance, via relay travel, from the Asari Republics themselves, and could expect a prompt response to a call for military aid, the system's heavy commercial traffic and extensive spaceborne transshipment and warehousing facilities invite the danger of hit-and-run commerce raiding; Illium's status as an asari colony, albeit not formally a member of the Republics or the Citadel governments, also poses the risk of politically-motivated attacks. Given the tactical limitations of ground-based and orbital defenses, no matter how powerful, Illium's founders included mobile defensive units in their initial investment of infrastructure in the system, and the planet's Board of Governors has subsequently expanded Tasale Fleet according to current threat projections and availability of new military technologies.
The fleet's flagship, and most powerful single unit, is the Vale Vigilant, a kelandion-type vessel manufactured by the shipyards of Epira. Built according to the specific requirements drawn up by Illium's Board in consultation with its serving flag officers, the Vale Vigilant is an oversize cruiser (commonly referred to as a battlecruiser) with significantly enhanced defensive capabilities, and fleet command and CIC facilities comparable to those normally found on dreadnought command vessels. Although Tasale Fleet regularly conducts training exercises open to public viewing - regarded as a reassurance to local merchants and a deterrent to potential enemies - the Vale Vigilant rarely participates in the full spectrum of manoeuvres when on public display; commentators speculate that the vessel's full combat capabilities may include restricted weaponry sourced from Illium's own R&D sector.
During the Reaper War the Vale Vigilant suffered damage during the initial battle, but afterwards rarely entered into combat with Reaper units except where isolated vessels could be picked off without excessive risk. Although Tasale Fleet's specific activities and tactics remains classified, it is widely held that the Vale Vigilant was kept out of major actions to ensure the survival of its command and control functions for the remainder of Tasale Fleet's surviving units. It is also speculated that the vessel carries QEC hardware; Illium's authorities announced that QEC comms were available in the event of conventional FTL blackout to reassure the public, but never revealed its location.
During the war, Tasale Fleet suffered heavy losses to Reaper destroyers operating in the Tasale system. The bulk of losses came in the initial Reaper incursion, when elements of Tasale Fleet fought a holding action against the Reaper spearhead to allow atomic-armed strikers the opportunity to close with husk transports and destroy them. This action, denying the Reapers instant ground superiority on landing, is largely credited with ensuring the survival of the planet's settlements. Subsequently the fleet's surviving warships moved to hit-and-run tactics more suited to the asari military mindset, acting to harass Reaper ships and draw them away from merchant convoys supplying Illium's besieged cities with crucial commodities, and deploy and protect stealthed FTL comms buoys to maintain communications with the rest of the galaxy.
The surviving units of Tasale Fleet, including its flagship, remain Illium's primary mobile defense, and have protected the system from opportunistic raiders and pirates on several occasions; despite their reduced capabilities, their opponents thus far have been similarly affected by the war. New light vessels have been commissioned from local shipyards, injecting a valuable government boost to Illium's shipbuilding companies, and among rumours that new heavy units are being negotiated for from out-system yards, there is persistent speculation that a carrier vessel is being considered as a potential acquisition.
The image of the Vale Vigilant is modified from a ship that appeared in Star Trek: Enterprise.