I'll let others define, defend, or justify science fiction. For me, it's just the way I like to read my fiction. For people like me, who're in high-tech, science fiction is a way of life.
This is an on-going set of reviews.
Midshipman's Hope, Challenger's Hope, Fisherman's Hope (series)
David Fentuch
If you've read and loved anything by C. S. Forester in his Horatio Hornblower series, you're going to love this one. A moody, almost neurotic midshipman, Nicholas Seafort, takes command in a spaceship (part of the U. N. fleet and patterned ridiculously close to the old British naval fleet) after a bunch of accidents knocks out his chain of command. He does well, and is promoted into further challenges that tax his integrity, mind, and identity.
Seafort is a very different ship Captain from the other well-known stalwarts of the field: Hornblower, Kirk, Picard. Shy, explosive in temper, poor in math, but an excellent tactician, strategist, and an inspiring leader, episode after episode displays his strengths and plays upon his weaknesses. The novels are written from the first person, so if you dislike angst-filled narratives avoid this series like the plaque. But if you like good stories, well-defined characters, and are hungry for something like Forester's series set in space, then you could do much worse than Fentuch's Seafort.
Octavia Butler
A story set in Butler's Mind of my mind series. Excellent writer that she is, Butler does not require you to read each book before proceeding to the next, and avoids the dreaded "trilogy" syndrome. A boy who's psionically powerful enough to rule the patternmaster culture (where might is right) escapes slavery and tries to make it to the dying patternmaster. During his journey, he learns humility, friendship, and to heal. This is not one of Butler's best, but on the other hand is a quick read and better than most drek out there.
David Weber
David Weber does not try to hide his debt to C.S. Forester. From the dedication in his first novel, to the name of his heroine herself (both Honor Harrington and Horatio Hornblower have the same initials), Weber pays his dues. His milieu is a Star Kingdom (Manticore) set in the far future, but for all intents and purposes is indistinguishable (again) from the British Navy. For instance: Manticore's government consists of a House of Lords, a House of Commons, and Queen Elizabeth. Even the ships have "broadsides" and "sails." Even traditions such as dueling have their place in this otherwise utopian setting.
There are differences: for instance, Weber's England, uh.. Manticore is politically correct: she is egalitarian, color-blind and race-blind. Her enemy is the decadent People's Republic of Haven, easily read as the welfare state that Weber sees the United States of America as heading towards.
But we don't really care about all this lack of originality, do we? What we pick up this book for is a good read, and Weber delivers. His heroine, Harrington is what every ship Captain should be. A brilliant tactician, strategist, leader, and manager, there's nothing she can't do. If needs be, she can use a plate as a shuriken, pick up a pistol and duel, fly an "ancient airplane", and fight like a samurai. She's described as beautiful (though she's too good a person to realize it), determined, and because of the technology prevalent at the time, is eternally youthful, and recovers from severe physical injuries to bounce back in time for the next novel.
I must admit it does get tiring reading about how wonderful Honor Harrington is. On the other hand, Weber's a good enough writer that the villains are rarely portrayed as being entirely evil. However, unlike either Seafort (see the Hope series) or Hornblower, Harrington is too perfect to be interesting (her only weakness seems to be an inability to do math --- another sign of Weber paying his dues to Forester). All her suffering is externally caused, and hence she never develops a depth that one finds in either Forester or Fentuch's works.
In summary, if you want good old space adventure, look no further, though I'd recommend reading Fentuch's books first. If you want to see interesting leaders and characters, I suggest picking up some military history, or re-reading Forester's books.