Please discuss this proposition: Violence as part of a public protest can never be justified.

This is very difficult because the definition of "protest"
is not a very concrete definition.

If protests are things
like the ones in England, which were touched off by complaints about police actions in
an essentially free and open society, violence cannot be justified.  The same goes for
protests against austerity measures in Greece and places like that.  These things are,
essentially, protests over issues that can and should be dealt with
politically.

On the other hand, if we define things like
what is going on in Syria as protests, violence becomes much more justifiable because
these situations are more like rebellions against tyrants.  The government there is one
that shows no signs of being interested in working anything out politically.  They are
attacking protestors with great violence.  In such cases, it seems that violence is
justified because it is being deployed against a much greater evil and against a
government which will not consent to political
discussions.

So, as long as protests are about things that
are not hugely evil, and as long as the governments involved would be willing to engage
in a political dialogue with the protestors, violence is not justified.  In cases like
Syria, however, violence seems much more justifiable.