I don't know that 'charging' is the right word.  If that's charging, then 'Walk for your lives!'

ATTACK OF THE KILLER TURTLE.

Awwwe, cute lil' thing... There must be a reason it thinks it needs to defend it's territory... I wonder what they did to agitate it?

In my experience snappers don't need you to do anything to be antagonized. Just you being there is enough. I do have to confess that I've made some snappers very nervous because I would approach them from the side to get a better look and they felt very threatened by it. Same thing with rattle snakes. I guess I have more curiosity than sense.

Ether the kitty was some cooter stew or the turtle wants something else.

They have jaws like some breeds of dogs, ones that lock.  And when they get locked they can hold several times their body weight, fierce little devils.  And, once they lock, you just can't get them open - though I'm told electric shock works, but it also gets you, since the turtle is still attached to you.

Tickling is the only answer - if it doesn't work on them, then it works on you instead .