People interpret different words differently. To many people dominance is a negitive word, while to others its the same as leadership. To me, a leader is dominant over a follower. To answer your initial question, As I veiw it, no you cannot have leadership without dominance, a herd member that is not dominant over its other herd members is not the leader, its a follower.
in some degree nearly every animal uses force to establish dominance to become a leader
Um, not really. A lead mare will only use force if absolutely nessesary, after several forms of obvious body language fail to get the point across. A wild stallion will use agression on an invading stallion only if he doesnt get the message, and oversteps the social boundaries. As owners, I think the same principle should be applied, asking a horse, telling a horse, then enforcing the command if absolutely nessesary(which it often is not)
being blunt here :
Anger is natural
Dominance is natural
Love is natural
Fighting is natural
in their appropriate place, and in ballance, yes. Watch a lead mare in her herd. How often does she get angry? I have seen the lead mare at the farm angry once, when she was first becoming lead mare. In the two years since then I have watched her ask, tell, and cooly enforce her possition. She disaplines only as much as nessesary.
Life is about ballance, and too much of one thing is never good, encluding the qualities listed above.