Actually I can't understand most of the players who carve words in stone like "WAR are useless" or "Not viable in endgame". The games mechanic changes from time to time so be patient and stick with your WAR if you like it. Of course there are players who will jump on the OP class train and switch to a job which is currently favored but I'm sure SE will tweak the class in certain way (or make a complete overhaul) of WAR tank mechanic. Personally I like WAR because it's not a cookie-cutter class where fail and success are close together.

Just take a look how often a class is changed in other MMO's. Finally it's certain SE won't drop a class in favor for PLD for example.