There is an honesty in the person who openly and directly opposes you that is far preferable to the less bold soul who, to use Elinor Wylie's words, has a smooth, ambiguous smile with lips that never part.
Some adversaries can be enjoyed and even liked. That cannot be said for the weasels who deny their opposition while doing everything possible to hinder and destroy your progress.
All of which raises the subject of weaselhood. There are two types of weasels: actual and perceived. The actual weasel truly does intend harm and employs slippery tactics in order to further that goal. The perceived weasel may not be a real weasel but indecision coupled with opportunism and a desire not to offend can exude the scent of weasel and thus destroy trust. Neither type has the attraction and integrity of a declared opponent.
Perceived weasels can be rather sad creatures since no den is their home. In an effort to be attractive to all minds, they fail to understand their own. Their worst sins are committed in the name of idealism and their introspection is so weak they don't even blush during acts of betrayal.
At least the actual weasel has the advantage of knowing what he or she is about. Actual weasels will not insult you by cloaking reprehensible behavior with sincere declarations of idealism. That is their odd form of integrity.