I have so many thoughts and opinions of this that I don't know where to begin, and it's not like I've had the motivation to read through old Naruto manga, so I may have forgotten a few things. However, I've read the latest chapter, so there's no point in telling me to wait for it to get better.
The so-called war is a failed concept to begin with. Ninja in the beginning were portrayed as killing machines working in small teams as pawns of politcians, which bothered our main characters, and after the final battle with Zabuza and Haku, both the readers and the characters were left with a feeling of hopelessness. What makes life worth living if you're doomed to spend your life as a pawn? Are you inevitably going to become like Zabuza if you get as powerful as him? Why were they forced to fight to begin with, considering they didn't even know each other? All of these are wonderful, difficult questions the reader is left with, and it makes us hope Naruto and his friends won't become like Zabuza or worse.
As the story progresses, we learn of other villages than the ones the protagonists come from, and we learn of the villages' common, bloody history. However, aside from maybe the Sand Village, these villages are never explored at all, so the only thing the reader knows about the different countries and villages is that they hate each other, and that there have been several wars in the past (of course, we're never really told why).
Fast forward several years, and all the different Kage are working together because someone in a mask claimed he was an old, supposedly super powerful warrior, and that he was going to take the remaining two tailed beasts. All of these Kage, who had been fighting up till now, decide to assemble an army as if they and the masked man reached some kind of agreement. After virtually no trouble, the entire army, save for a few characters like Naruto who is off training on a special Jinchuriki island that had never been mentioned before, is standing in front of their commanders. Since a lot of them remember the wars of old, there's a lot of fighting among the ranks, which is perfectly understandable; after all, half of Shippuden has basically been about Naruto wanting to find a way to create lasting peace in the world.
Luckily for Naruto, Gaara takes care of that with one speech. I'm not kidding, after one speech, the entire ninja world is prepared to stand united; the nameless soldiers all forgive one another, and the trust issue is never once brought up again.
So yeah, Naruto's big dream of uniting the world, a dream inherited from his teacher, was accomplished in the span of a minute or two. The best thing is that it wasn't even he who did it.
That's one of the worst things in the war arc, but don't worry, we've got plenty more shit to wade through.
So what are these redshirts going to be fighting? Clones. Clones and zombies resurrected by an uninteresting villain - consider him an evil version of Smithers from Simpsons, because he was quite literally the butler of a much more intimidating villain. His name is Kabuto, and he somehow stole some powers from his old master because he wanted to be noticed by people, so now he resurrects zombies and kill people from afar, which is the perfectly logical thing to do.
While I'm at it, I might as well describe the motives of the two other villains.
The masked man's 13-year-old crush died.
The villain sue's brother died.
And now they both want to create a world where every dream can become reality. Once again prime examples of moon logic. But we'll talk more about those two later.
Kabuto, or rather, Japanese Smithers, starts resurrecting zombies which need to be sealed, since you can't physically destroy a soul. These zombies, aside from the villain sue and the creator's pet Itachi, barely impact the story in any way, and are just there to stall for time. They're souls of former great Ninja that we've never heard of, and since the support characters are completely worthless, they have to wait for Naruto or maybe a Kage to deal with them while they stand there and stare in awe. He also brings back old villains who get thoroughly humiliated just for the heck of it, an old sensei who had already had a proper farewell with his students so that fight was completely unengaging.
Oh, and by the way, there are 100.000 clones vs 80.000 Ninja. Considering that we only really see either corpses, zombies or characters with names, the armies are literally doing nothing for the story.
Anyway, remember the creator's pet Itachi and the worthless support characters? The latter have been thoroughly ignored for years, and are currently stuck in circles waiting for Naruto's help, afraid of the clones that can imitate them perfectly, so now the dead Itachi, whose character has been a walking oxymoron and a source of several bullshit jutsu, somehow breaks the zombie spell and decides to go and teach Japanese Smithers a lesson by teaming up with his evil brother and using yet another jutsu we've never heard about. So rather than having Naruto's friends do SOMETHING of value, we have to deal with Itachi's plot armor yet again.
Oh, and that evil brother is basically supposed to be Naruto's foil and motivation, but he tends to warp the plot wherever he goes. The best example I can think of is how he summoned a snake, cast a genjutsu on it, went inside it and teleported just to escape an explosion...
when he was so hurt he couldn't walk and didn't have any chakra to do any of those things. Anyway, once Itachi employs some talk no jutsu, Sasuke turns sort-of good. Once again, one of Naruto's goals are accomplished in five minutes by someone else, making both him and the support characters look completely ineffectual in the process.
Anyway, the zombie spell is now broken, but the villain sue naturally knows how to cancel the effects, so he's safe. He's currently fighting (and completely dominating) the leaders of the five larger ninja villages. He's revealed to be the source of pretty much every major conflict, knows absolutely everything about things worth knowing about, has access to some secret techniques by stealing a certain type of DNA which is being passed around more than a condom at Woodstock and throws around insults like a spoiled brat. We never know the reason why he's so strong in the first place other than that he was born into a powerful family, like pretty much every douchebag in the series. I could talk about that for a long time too, but my rambling would get even more confusing.
Anyway, he almost kills them all offscreen because hey, he's got to help the masked man who's fighting against Naruto.
Naruto breaks the masked man's mask with one of his strongest attacks, so logically there shouldn't be a face left but hey, whatever. It is revealed that he's Naruto's sensei's old comrade; the first really good moment in the arc. It fits the story, and there's a lot that could be done with this. Unfortunately, that doesn't happen.
Once his mask is broken, his calm persona is more or less shattered and he starts raving about his 13-year-old crush who died some 20 years ago. Then we're forced to deal with flashback after flashback which pretty much guarantees his future face-heel turn. We're also treated to speech after speech of Naruto's ninja way, the power of friendship and the importance of working together (pretty big words from the masses who were convinced by one speech). Over the course of maybe 20 chapters, I believe we have around four of these speeches, and once again I'm not exaggerating.
After speeches, villan sue insults, masked man's monologue about his hurt feelings and the depressing world they live in (which once again take many chapters), they're seemingly defeated. Except the villain sue had more or less planned this all along, becomes even more powerful, defeats the entire army by himself/forces them all to retreat, leaving only characters with name and further proving how unnecessary the armies were (at this point, the clones have also completely disappeared without a word) and the masked man is currently working on his redemption, something that was predicted years ago.
There are many, many more things to talk about that also deserve to be mentioned, but I've been working on this here for a while now.
Oh, but there's one final thing I should add: over the course of these two, three years of "war", I believe one character with a name has died. One. He had a role in the first season, spent years being ignored, died, then he was never mentioned again.