Does Holden's description of how he would deal with the “glove thief” support his pacifism, or is he just “yellow” in The Catcher in the Rye?

I think that Holden might be "yellow" in this instance. 
There is much to indicate that Holden contradicts himself so much that he lacks the
moral certainty and fortitude to effectively embrace pacifism.  Yet, even if this is put
aside and we take a leap to presume that Holden is a pacifist, his analysis about how he
would not effectively confront the glove thief is not rooted in a set of pacifist
philosophical beliefs.  Rather, he simply accepts the fact that he is not able to follow
through on his desire for retribution.  He admits to being "yellow," but it might also
be reflective of the lack of direction and focus in Holden's value set and his life. 
There is much in way of misdirection in Holden and his inability to confront the glove
thief is a part of it.  This same inconsistency is evident in his accepting of the
prostitute, even though he has previously claimed that "sex should be in a
relationship."  It is also evident in his inability to follow through with being in the
prostitute.  The emotional impotence of action in Holden's state of being in the world
is what defines Holden and it is evident in this moment with the glove
thief.