I've just been involved in a conversation regarding the Military Human-centric Dictatorship disguised as a peaceloving alliance that is the Star Trek Federation and Starfleet.
What percentage of children in Star Trek go into the military? All of them. Those who don't become ostracised from humanity and by necessity move into the fringes. While the federation claims mankind has moved beyond money, it's more the truth that everyone is catered to by the military machine.
The president of the United Federation of Planets (generally but not exclusively a human role) is often left powerless by a variety of Starfleet officers, making it clear that the Federation is a cover for the military Junta running Humanity since the days of Khan.
"Scientific / exploration" is generally out there for the purpose of finding minerals to fuel the military machine (how many mining outposts does the universe have - and why is it whenever a mining colony slips behind quota a large and heavily armed starship is immediately dispatched to "provide assistance".)
Further to the exploration questions - on the rare occasions when humanity has obeyed it's own "Prime Directive" and not made contact with another species until they reach a certain level of technological advancement, one of two things happens - they are absorbed immediately into the Federation 'for their own protection' (FEDERATION = MAFIA?); or WAR is declared.
Klingons? WAR
Romulans? WAR
Ferengi? WAR, then trade (despite apparently not needing money anymore)
The Dominion? WAR
The prime example of the military nature of the Federation is not DS9, despite its being mostly about a WAR.
It's Voyager - in which Janeway sacrifices lives repeatedly, ostensibly to save the ship but more to satisfy her ego. She manages to get into large scale conflicts with a number of races - all of which are recognisably not a threat since one ship holds them off repeatedly.
Further, the great "Prime Directive" is Janeway's guide to what not to do. She ignores it consistently, promotes war criminals to her assistance, demands unfailing loyalty from all races repeatedly, including the identityless Borg and her own ship's AI.
Having thoroughly demonstrated for seven years her disregard for her crew, her mission of 'peace' and the idea of peaceful solutions, upon her return to Starfleet - Instant promotion and cushy job! SHE SHOULD BE BLOODY SHOT!!!
I could get more into it - the regularity with which every away team lands and draws weapons instantly against even bikini clad serving wenches. Spock mindraping his own lieutenant in Star Trek 6 for the sake of a military alliance. Worf as a kidnapped and indoctrinated symbol of the Federation's "Better" status. The universal inclusion of a tactile or greater level psychic to help maintain the status quo. Simulated food with the bare minimum of nutrients required.
You know what, I should really stop...