Conflict

it doesn't take much skill to pummel the living shit out of someone (just got to be damn dua jia...). but to coerce him to move in the way you want him to, gently introduce his skull to the ground and persuade him to submit without injuring him (too much), that takes much skill...

my favourite Aikido story by far:

this gaijin (brit, american, whatever, you choose...) just got his shodan in Tokyo. he was riding the train somewhere. in the same carriage was an old geezer (the sort that has all the signs of ancient wisdom etched into his face), a drunkard and a pregnant lady. the drunkard was being unruly and started to throw insults at the pregnant lady. so this gaijin thought, 'yar, just give me a reason. i've just gotten my shodan. let me make some good use of it and break you in 2.'

and true enough, the drunkard got more and more abusive and started getting physical with the pregnant lady. at this point, the gaijin wanted to get up and show off his powerful Aikido. the wizened old man stopped him before he could. then the old man looked at the drunkard and started talking to the drunkard, asking him why he was doing what he was doing.

the drunkard, of course, told the old man to piss off and mind his own business. but the old man persisted. the drunkard started shouting something about how the world's unfair, how he lost his job, etc. and before long, the drunkard broke down and was reduced to nothing more than a babbling baby at the lap of the old man. apparently, the drunkard had lost his job and his wife ran away with someone else. and so the old man comforted the drunkard and showing empathy.
the gaijin realised that that was Aikido (the way of Harmony) at its highest level.

Sun Tzu, he say, "to fight a hundred battles and win a hundred battles is not the way of the best strategist. the way of the best strategist is to win without even having to fight."

it is of course difficult when you try that with people's minds/beliefs/opinions. it takes greater skill to manipulate people's thoughts, beliefs and emotions than to manipulate their bodies.