growing activism

Salaam,

I am wondering how those of you who are activists on a
large(r) level know when what you are doing is
useful/working?  I'm coming at this from the
perspective of the smallest.  Give 1 person some food
& he is not hungry for a day, shelter and not out in
the elements for the night.  It is very clear what is
working at that level. it is easy to see if someone
stops drinking or stops using drugs. it is easy to see
if someone hasn't killed themself.

As the target of the activist increases past the very
small, how do you know if your meetings, speeches,
protests, etc., are doing any good?  How do you
measure it? Is it a "feeling" thing?  Is it a level of
opposing intensity measurement? Is it the
acknowledgment of others like yourself?

I see this as somewhat separate from the "do the right
thing" need that we probably all have in that I think
that the "right thing" is irrespective of
outcome--more of us having a whiff maybe of what God
has put us here on earth to do. 
wondering, Vana