I don't see "all these level 70 paladins and druids and I can't find a tank" nearly as often. Now, I understand that paladins and druids can heal, and the general populace finds that to be just as valuable. But I know there are a host of DPS druids and paladins out there. While they're derided to some degree (and unfairly so, but this column isn't named Matthew Rossi defends every one of the tanking classes if they choose to DPS - we know it's unfair, we'll let it go at that) there doesn't seem to be this absolute assumption that the first and best role of any class that can tank is to tank the way it seems to be there for warriors.
Now, I love tanking. I'm good at it, I enjoy the challenge, I stay up all night working on threat sets, avoidance/mitigation sets, stamina sets, I go to sites like Wowhead and look at shields all day. Tanking is my idea of a good time. So I'm certainly not arguing that warriors cannot, or should not, tank.
I'm arguing that they should not tank just because you want them to.
If you happen to be so desperate for a tank that you're berating someone else for not choosing the role, you might want to consider why it is that you're not a tank yourself. Why aren't you tanking? There's nothing stopping you from rolling a druid, a paladin or a warrior (and death knights are on the horizon) and tanking to your heart's content. It's possible you started playing with a specific class concept in mind... the stealthy rogue, the determined and willful mage, the cackling warlock raining destruction down upon his enemies... and you don't want to play another role. Since that's fair enough, let me ask you why the up and coming warrior should be forced to play another role than the one he envisioned to suit your needs, since you're not willing to make that choice for him. He leveled his character to 70 expecting, as far as you know, to DPS his way through instances the same way you did.
Furthermore, we all know the reason the vast majority of players don't want to roll a tank: because tanking is hard, and furthermore, tanking lowers your viability to do anything but tank and can even cripple it until your alternative gear selection is good enough to compensate.
Tanking isn't impossible, it's not rocket surgery or brain science. Or whatever. I take a lot of blows to the head, you can't expect me to remember every cliché properly. But while tanking isn't this impossibly difficult thing, it's not easy either. It's hard to learn, especially when you've never done it before, even harder if you're learning to do it in a pick up group with people you don't know who aren't scrupulous about their threat (do most PuG's even use Omen?), don't follow a kill order, may not even mark their targets or expect the brand new tank to do it, etc etc. These awful runs are learning experiences for the new tank, yes, but often what they teach him or her is that tanking sucks and they run back to a DPS/PvP role as fast as their fingers can carry them to the trainer. And it's hard to fault them for that. Sure, if they stick with it, they'll eventually develop the kind of berserk reflexes that lets them smash a shield slam into the face of a mob that's about to peel and then immediately intervene to the healer and thunder clap two mobs off of him, but it's hard to make that fact clear when they're staring at a massive repair bill and being berated by the people who hectored them into tanking in the first place.
As a prot warrior, I can't complain about grinding or questing anymore, really. I have roughly 2000 attack power, 30% chance to crit, and a ton of hit and expertise in my DPS gear. I can devastate spam and put out very respectable DPS and quest my way through the dailies, easily making myself 200 to 300g a day without effort.
I am in Black Temple/Hyjal content. My DPS gear is the stuff nobody wanted out of SSC/TK/Hyjal anymore. (You can see it in the picture that accompanies this post.) Believe it or not, the average 70 warrior just starting out does not have DPS gear even close to this good unless he was grinding battlegrounds like a fiend the whole time he was leveling and stockpiled enough honor to pick up all the Season 2 gear as soon as it went live for honor. (And even then he'll be significantly short of my attack power.) A protection warrior in the greens and instance blues most common to leveling to 70 is a hobbled, wretched thing barely able to put out enough DPS to kill one mob before the one he killed before it respawns, and this assumes he's been lucky enough to collect some decent DPS gear along the way. And if he hasn't... if for some reason he leveled to 70 tanking in instances with a group of friends or even ran endless PuG's and didn't roll on DPS gear at all and is now running around the Isle of Quel'Danas trying to kill naga with barely 400 shield block value for his tiny little shield slams... then his daily soloing or questing is pure, unadulterated torture. Heck, I have the gear to do it, or to run around with my tank gear on and whack things with nearly 2k shield slam crits, and I still find it to be boring and tedious compared to how fast I can go if I drop the 50g for an arms or fury respec.
I'm going to repeat this premise for emphasis. It is not the well geared, raid level protection warrior in excellent DPS gear who is hobbled by prot spec, it's the newly 70 warrior in the crap gear out of the AH. It's the guy who you want to start tanking so you can get your instance runs. I'm usually too busy tanking raids to help you, I don't need to run normal Black Morass, and I actually tank with pieces of my gear off to make sure I have enough rage when I run heroics. I'm doing fine. It's not me who needs help, it's that poor guy over there who looks like a rodeo clown in his greens trying to hold aggro against DPS geared in full PvP epics and then, after that carnival of fantastic awesomeness, gets chewed out for not holding threat when he only tanked the run because he got nagged into it and now has to go out in that same awful gear and run dailies just to make enough gold to repair that crap and sign up for yet another heroic Mechanar in hopes that the Sun Eater will drop. Even though he knows if it does some rogue or another will roll on it and win. Not that I remember my times in the trenches running PuG's in awful gear with any sort of frothing, incoherent rage or anything. No, the amount of crap I had to swallow from undisciplined DPSers who don't know what focus fire is, can't follow a kill order, and want me to somehow magically tranform into a paladin and AoE everything so they can nuke as though someone just cut off their ritalin supply didn't jade me, but it did open up an inexhaustible supply of compassion for the newly minted 70 warrior who didn't really understand what he or she was getting into.
If for some reason you rolled straight into Karazhan in Tier 3 and started getting purples, then this doesn't apply to you. A lot of us didn't do that. I took six months off from WoW just before The Burning Crusade hit, I was guildless and undergeared by that point. Some people started warriors after the expansion launched!
It's not really protection spec as such that limits you, it's the gearing issue. That's part of the game to some extent... obviously in order to get better gear you need to run instances for reputation and drops, and that goes for tanking gear as well as DPS gear. You can't expect the newly minted 70 to just be handed Tier 4 in both flavors as soon as he dings. That's why I'm hopeful that in Wrath tank gearing for warriors will combine with new tanking abilities to make protection soloing and grinding viable for the newly 80 warrior in the Northrend equivalent of the Felsteel set and whatever greens with defense he picked up off of a boar somewhere.
Finally, I want to make one last point about why not all warriors should tank.
Not all warriors are good at it.
It isn't impossibly hard, no, and even unskilled tanks can learn how to do it well enough to hold aggro fairly well if nothing goes wrong and their group throttles back on DPS. But some people are just freaking awful. Some of the worst experiences of my gaming life have been on my alts running instances with a tank so bad he didn't even spend his talent points after he paid to respec. He forgot. And when I inspected him, saw that he had no talent points spent, and pointed this out to me he hearthed because he believed he had to be at the trainer to spend them and even spent another fifty gold to respec in order to be able to do so.
One of the premises of the improvments to druid and paladin tanking was that it would allow more warriors to be DPS. It was a nice theory, but it hasn't really worked out: most groups who take a warrior only take a non-tank warrior if he or she started the group in the first place. But frankly, some warriors shouldn't tank for you. You don't want them to tank for you. (Of course, some of these warriors are also bad at DPSing and can't PvP either, but we're not here to tell you to avoid bad players in general, that's sort of a given.) One of my first mentors in the game was a fury warrior who was exceptionally talented and skilled at fury, and understood the theory and math behind it intimately. He couldn't tank if you strapped a picture of Ragnaros' mom with dirty limericks written on it to his shield before you talked to Domo. If you sent Nefarion a video of Onyxia's corpse being teabagged by him I don't think he could have held Nef on him for ten seconds. Nice guy, great player, smart DPSer, loved to help people, worst tank I have ever seen. It was like he was wearing the shield on his feet or something. You'd love to have him in a group, he knew all the instances and the bosses intimately, he was a solid, guaranteed source of high DPS, but the only way he was going to hold aggro as a tank was if you let him dual wield in DPS gear and just spammed heals until you were out of mana.
In the end, I don't expect the addition of a new tanking class to end the tank shortage. I see some hope for it easing with new talents for all tanks, the idea that itemization should change to make tanking specs more solo friendly for those without the luxury of full DPS sets, and another tanking class. In the end, though, the reason there aren't as many tanks as people might want is because of people being people. I don't think that's going to change any time soon.