I, and others, will calm and/or kill the NLC mercs in the same way we do the Sentinel thugs in Tir right now. I encourage everyone to either keep the NLC mercs and TIr thugs calmed or dead on a continual basis.
As for those that hired them...the first innocent they kill makes all of YOU murderers...so don't be surprised if prices are put on YOUR heads and you find yourselves hunted down and your guilds bases continually destroyed. This you have brought on yourselves and I am pretty sure you won't like the result.