What Makes it Kung Fu?

[Kellen Bassette]

If you strip out the forms, style specific drills, traditions, Mandarin/Cantonese and leave only fundamental fighting technique, what, if anything makes it Gong Fu?

All good fighting tends to be similar at the base application level, so what makes a fighter "Chinese?"

Is it the way you do your cross or sidekick, the stances/footwork you apply, your theory/philosophies, the core drills, a particular pattern of attack or defense?

Aside from stylistic preferences, sport rule sets and such; at the base level, what would be the difference from a Chinese, Japanese, Thai or whatever based fighter?