If she learned military hand to hand combat. She will be one very dangerous woman.
I know that in the US Military we have men who are extremely physically fit and physically flexible like that for exactly this reason.
Sometimes, Rifles knives and hand held missiles or the American war technology are not an option.
They send in hand to hand combat teams that specialize in taking out enemy personnel.
Leaving no trace that the United States Government was having ever been there.
That will make even the most toughest , experienced and battle scarred enemy soldiers become so scared and have living , walking nightmares and the enemy military commanders will be very murderously angry and so frustrated, more and more determined than ever to kill the very dangerous U.S. soldiers who are able to appear then vanish without a trace at will.