Zeratul is not a leader in the same sense as Tassadar and Fenix. See, when we say "leader", we think of people steering by their own vision or those that make plans to see these visions through. We don't think of people whose authority is limited to a narrow field. See, potentially anyone can be a kind of leader. There is always an opportunity or situation where you or anyone else can take charge, even if it's something as simple as a school group project. What we call natural leaders are those that can take charge without extenuating circumstances, or can find a place for themselves in authority. However, just because someone isn't a natural leader doesn't mean they're not a leader.
This is where Zeratul comes from. A lot of fanfiction writers, but not all, have guessed that Zeratul would become Patriarch in Raszagal's place (the ones that don't pick Artanis, that is). This is natural, what with Ras' comment on asking him to protect their people. This, however, is the exact wrong place for Zeratul. He can possibly fulfill his promise, but not as a Patriarch. He's not that type of leader.
Is Zeratul a Visionary? No. He is extremely depressed, and does not appear to have any vision of how the future can improve. Is he a Strategist? No. It's true that he's detail oriented. Thing is, he's TOO detail oriented. He's not available for large scale strategy, but small scale tactics.
Think about it. What was Zeratul doing before the events of Starcraft? From his comments he makes to Aldaris, it's pretty clear he was an explorer, someone who wandered the universe at his own curiosity. Zeratul also makes a comment that indicates he may have secretly protected Aiur, and this is confirmed by the fact he knows where it is. He's not a general of strategy or someone who works at Raszagal's side to care for the Dark Templar population.
Next, what does Zeratul do during the events of Starcraft? He works for Tassadar, killing cerebrates. He orders no one around, and seems fine with letting Fenix determine general strategy. During Brood War he attempts to take on some normal leadership roles, what with leading Aiuran refugees to Shakuras and going on the quest to get the crystals Uraj and Khalis with Artanis. These missions are reasonably successful, but fraught with failure. For one thing, Zeratul doesn't appear to see that it's not a good idea to provoke the Earth Directorate, when it's a fight he could potentially avoid and a chance to create peace between humans and Protoss. Secondly, he spends a good deal of time with Kerrigan, and does not perceive her intentions. His focus is only on gaining the crystals, which he does.
After this, Zeratul's actions are unknown until he is told to destroy the new, fledgling Overmind by Kerrigan and Raszagal. Not knowing or guessing the treachery involved, Zeratul does not choose to question Raszagal's order, or why she so readily agrees with Kerri to go after the Overmind. He doesn't come up with some plan to rescue Raszagal, or order those with him to set up a quick escape. Zeratul simply does what is obvious and destroys the Overmind. And after all this has gone down and he was forced to kill Raszagal, he simply disappears, presumably to find more of the hybrid specimens and what he can learn from them.
It's not that I'm trying to say Zeratul sucks (that doesn't come until SCII), it's just that he's the opposite of the Visionary. The Visionary sees the big picture at the expense of the small. The Operative, what Zeratul is, sees the small picture at the expense of the large. It's not a disadvantage, it just means that there are certain places where the Operative is not appropriate in authority.
The reason why Zeratul is so depressed throughout Starcraft is not so much his circumstances, but that he feels incapable in his circumstances. He probably knows it's his fault the Overmind found Aiur. He might blame himself that the Zerg followed them to Shakuras. Zer likely blames himself for bringing about Aldaris' death and not noticing Kerrigan carrying out her plans. He definitely blames himself for Raszagal's death. Possibly he feels guilty that he left his people at the end of Brood War, comforted only by the fact that he really had no choice but to investigate the Protoss-Zerg hybrids.
This is where I must point out that Starcraft doesn't only show leaders doing well, but also their weak sides. Tassadar and Fenix did mostly well, and so they're examples of how the Visionary and Strategy leaders operate in more or less ideal situations to show off their abilities. The primary Operative character, Zeratul, is in several less than ideal situations, where he is "over-promoted" due to the hard position the Protoss are in. Artanis is even more over-promoted, but we'll get to that later.
So let's look at Zeratul's successes, and why everyone thinks he's so cool. While Zer has a lot of failures, he also has many opportunities to show the true purpose of an Operative. An Operative is someone who is not necessarily a low-authority person, but rather a small authority person. Simply put, the Operative works best surrounded by a small group of highly trained individuals, or alone with lots of independent ability. Operatives don't like dumb questions. They want to accomplish things and move forward, and it's a struggle for them to work with novices or lots of constricting rules.
Operatives get very specific jobs done: jobs with one specific goal in mind and open-ended means of accomplishing it. The Visionary decides what to be done; the Strategist figures out what must happen; then the Operative is chosen for specific, detailed objectives, not general combat. Operatives do things like get data discs off ships, assassinate political figures, and go on extensive reconnaissance missions. This is the basic definition of a Dark Templar -- a secretive person in the shadows doing things no one understands. This isn't to say that all Dark Templar are the same way, it's that Zeratul as a character is representative of what Dark Templar culture is in Starcraft.
For the sake of describing an Operative, let's focus on what Zeratul did well. He killed Zasz, two more cerebrates on Aiur, snuck up on the guards around Tassadar's cell, aided in the destruction of the Overmind, gathered up Aiuran survivors, and killed the fledgling second Overmind. What do all of these have in common? They are situations were there is a clear, singular, smaller goal. It's something Zeratul can do while greater forces cover his back.
Zer never took over a city or laid siege to a base. Those things are larger in scale and require a lot more patience. Like the Visionary, he has to do things and is unable to remain static. Unlike the Visionary, he's not driven by vision, but by accomplishment. That's the key word of the Operative, and why Zeratul is so very depressed at the end of Brood War: he feels his accomplishments are few and meaningless in comparison to his failures and believed failures.
Poor Zeratul. If he's going to amount to anything in his own mind, he's going to have to embrace his narrow form of leadership and trust himself to do those tasks well, as well as asking help from others who are more big-picture oriented.
As I am unfortunately obligated to consider Starcraft II canon, a thing I don't generally do, this emphasizes Zer's inability to understand the bigger picture all too well: Zer attempts to help Kerrigan in the effort to make her face the Protoss/Zerg hybrids, while failing to realize or appreciate that giving Kerrigan power will enable her to kill a lot of humans and Protoss. Which Kerrigan then promptly does. You might argue that Zer is understanding the bigger picture by sacrificing those people for the sake of everyone else, but is that really a case where the ends justify the means? I, however, refuse to believe the real Zeratul is that friggin' stupid, so for the rest of this blog I'm going to pretend SCII does not exist.
I might have said earlier that Operatives work well alone, but this is only in the short-term, in the sense of performing an objective. As soon as a Visionary tells an Operative to do something, like say infiltrating a spaceship for discs, that Operative can complete the task either alone or with capable partners. However, the Operative still needs help in choosing which spaceship to infiltrate, and whether or not infiltrating it is a good idea. Operatives are so detail oriented that they think too in-depth about every possible situation, and thus need help prioritizing what needs to be done, so that their analytical skills can be put to use on the right topics.
It's like in economics: positive vs. normative analysis. Positive analysis means working in raw facts and details, limiting one's statements to things that are verifiable. This is the strength of the Operative; if we infiltrate this ship then we need to deal with this security measure and this many enemy guards on the ship. Normative analysis, the weakness of the Operative, is an analysis based on value judgement: if we have the raw data, then should we use that information this way or that? Is the information on the disc really worth risking human-Protoss relations by infiltrating a human vessel? Should we share this information with opposing human forces or just keep it to ourselves?
The overall point I'm trying to make with this blog series is that all leaders need each other in one way or another. Tassadar could hardly destroy the cerebrates without Zeratul's details, and without Fenix's plans Zeratul and Tass would be out of luck on how to best go about breaking through Zerg forces in order to reach the target cerebrates. Each personality is a puzzle piece to the bigger picture.
Like the Strategist, the Operative is very present tense in focus. He may appear somewhat past-tense in examining history or the highs and lows of his accomplishments, but all in all the Operative must see things as they are, rather than what they were or what they will be, in order to perform at his best.
As far as promotion levels go, Operatives are best not promoted to higher positions that would take them away from specific, detailed oriented missions. However, unlike the Strategist, they can do fairly well if they have to in higher positions, as long as they have a specific goal for what they want to do in that position. For example, a President who is also an Operative may want his administration to focus on helping the economy. Said President might not be the best on foreign relations, healthcare, or social interests, but his detailed mind would be able to absorb all the different ins an outs of the economy, and he would know what about tax codes, foreign tariffs, and budget issues all need to be changed.
Note that if Operatives do have higher authority, they are far better as peacetime Presidents (or somesuch) than in wartime. It's difficult to keep a full eye on something like the economy when there's a more radical issue on the map, and the Operative's mindset will direct them towards doing something in that area and leaving other issues neglected or simply worried about, feeling that they have insufficient time to deal with them.
Lower authority doesn't really work for Operatives. Granted, they can do menial tasks (can't everyone?) but they work best in areas where they have at least a little control of things, and can use their detailed mind to find efficient ways of doing things. The place where Operatives stagnate are the places where the existing higher authority ignores or constantly refutes everything the Operative wants to try to do. This is one reason why Zer appreciated Raszagal so much: she never restrained him from exploring the universe or attempted to control his efforts in the fighting on Char. Operatives need an environment where people care about their opinions, or else they'll grow bitter.
Also, the Operative doesn't necessarily have to be military in nature. For example, an environmentalist Operative may only care about saving a certain animal in a certain place, and will exclude all other locations in his thoughts (and potentially opposing views). This Operative may be content simply to make this one environment a pleasant place for his chosen creature to live in, and just study it all his life, writing reports back home when it suits him.
As for Zeratul, let's examine the things he needs to do. For one, he needs to forgive himself his weaknesses. Nobody is perfect at everything, and if he can understand the points where he hasn't done so well, he'll know in what topics he should ask for help. Two, he needs to think of alternatives and opposing sides to his own impulses. He failed this two major times, in that he didn't think out why Aldaris could have had a point in rebelling against the Matriarch, or why he possibly shouldn't have done what Raszagal said and avoided or delayed attacking the new Overmind. Granted, he may have had to act the same way in both cases, but had he thought about things through, he may have found better ways to solve his problems.
Three, he needs to ask for other people's help, and not just listen to Raszagal all the time. When I get into Raszagal's blog, I'll explain in detail, but for now I'll just mention that Ras is a Steward type leader, not a Visionary or a Strategist. She therefore is less an action oriented leader and mainly about taking care of what already exists. Zeratul needs help from people Tassadar to help him get a better grasp of the bigger picture, and also to shake him from all that depression. After all, if a Visionary can see a great future better than today, it gives Zeratul hope that his actions are not in vain.
A form of leader concerned about specific goals and events.
Key word: Accomplishment
Authority level: Higher (in peacetime) to middle
Operates best: With a cluster of highly trained and trusted partners
Operates worst: Without higher authority or Visionary guidance
Potential weaknesses: Bitterness toward constraining authority, depression without achievement
Ultimate vulnerabilities: Lack of perceptiveness or big picture view, need for trust