the way that leon and his line of work, the job he never wanted and finds himself in too deep to back out from even when the threats of the initial blackmail have faded as sherry aged and government power shifted, draws a line between him and everyone left in his life. years of isolation, mission after mission. he builds up enough of a reputation to his name that he claims certain freedoms, his word is trusted, he gains a bit more power in the foundation of the DSO yet finds himself the most disillusioned he has ever been. BSAA and terrasave are different organizations, sure, but it is easier for them to work hand-in-hand— leon is at the whim of the american government, held to assignments and either running into the others by coincidence or going rogue.
but as much as it is his job, it's simultaneously leon holding HIMSELF at an arm's length. he is constantly pushing back, but fear of what may happen were he to step too far out of line has a tendency to make him complicit, and his entanglement with american forces poses the risk of even his closest connections not quite trusting him with everything. leon doesn't trust his own position, he understands, he pulls himself away often because of it, but it still eats away at him. it's yet another reminder that even if he's learned to work around his restraints, he isn't really free.