Laguna's story is unique for an RPG character in that it spans decades, and we get to see Laguna in a variety of professions, from his days as a Galbadian soldier to his tenure as President of Esthar. Along the way he is a journalist, a really bad actor, a revolutionary and possibly an astronaut. We're going to focus on the main ones here, though.
When we first meet Laguna, he is serving with the Galbadian Army in the war against Timber. He is the leader of a small regiment that includes Kiros and Ward. How Laguna got to be leader is anyone's guess, as he has a real problem with navigation and keeps getting lost and forgetting maps. Still, with a little more prodding, we see that Laguna is a natural leader and that Kiros and Ward both trust and respect him, despite his naviational shortcomings.
When Laguna and his company are surrounded by Estharan soldiers, he throws Kiros and Ward off a cliff in a bizzare attempt to save their lives. (It works, by the by, it just seems a bit counterintuitive.) He saves them first, before attending to his own life, which is in equal peril. He puts others before himself, and we see a bit of what makes him such a great leader despite his blatantly obvious faults.
I think it's important to note that Laguna is a citizen soldier- the military is not where his heart is. In contrast to the elite missionaries known as SEEDs, Laguna is not a career soldier. His dream is to become a journalist, and he knows that his time in the army is temporary. At the core, he is no fighter, though I would be hard pressed to call him a true pacifist. No doubt he's glad for the experence and friends the army gave him- he's still wearing his dog tags in the game's closing sequence.
Laguna's ambition was always to be a journalist. He dreamed of using his words as an instrument of justice, to right wrongs and write rights. Durign the game we learn he did acheive at least part of his dream. He travelled the world writing articles about the people he met and the places he'd been, and they were all collected in the Timber Maniacs magazine. You may have been expecting something a bit more grand from our justice-seeker, but travel journals are a time honored form of jounalism practiced by many famous authors, including Alexandre Dumas and Queen Victoria, and it was how Mark Twain got his start. No doubt Laguna's ambition would have carried him further had not life and love interfered.
Journalism is a career that mixes purpose and art. To be a good journalist, one must have a mastery of the language and to know how to tell a story so people care about it. It offers a lasting form of immortality through articles, and a chance to change the world using words and not action. It's not hard to see why Laguna wanted to be a journalist, with his peculiar set of gifts.
You can find copies of the Timber Maniacs in these places:
When the President of Esthar contacts Squall's party and tells them to come to his country, it is revealed that the president is none other than Laguna Loire, whom the party has been dreaming about for some time. Laguna gives the party a plan to defeat the evil Sorceress Ultimecia.
He got the job some years earlier, when Ellone's kidnapping led him to Esthar. The people of Esthar are ruled by the evil Sorceress Adel, Ellone's captor, and Laguna decides to help them free themselves. (This is, after all, the sort of thing he lives for.) Thanks to his natural charisma, the people elect him leader of the resistance movement. Laguna comes up with a plan to put Adel in suspended animation, and when it succeeds, he becomes a hero and the people elect him President of Esthar.
As president, Laguna's only major act of policy that we're aware of is to shut the country off from is neighbors, in penance and in order to protect the world from Esthar's advanced knowledge and/or time travel machines. This policy reeks of the Embargo Act of 1807, but I'll spare you my rant on that. Anyway, this descision is sort of questionable, but he's Laguna, he can get away with anything and be re-elected the next year. He is a good leader and for the duration of Laguna's presidency there has been peace. Except against evil sorceresses, but they're evil. His plan does manage to defeat Ultimecia and I'm sure that will give him a big boost in the polls next year, even if the isolation is ended.