[quote=@Kingfisher]
<Snipped quote by TheUnknowable>

I'd suggest that it might be worth also playing the character who the Mr Handy was tied to, just so you weren't limited.  
[/quote]

He's autonomous, though he is programmed to be part of a hierarchical command structure.  His heuristic algorithms blocked that command chain from being valid, however, due to there not being a valid authority figure for him to follow.  The Enclave isn't the actual US government, and he's loyal to the real, pre-war US Government.