It is
simple and
well-known, still some people seem to have
difficulties with the concept.
It does not depend on the
cause you fight for. A cause which seems
fair enough to some, may look
unacceptable to others, and sometimes it is extremely difficult (not to say
impossible) to decide who's
right and who's not. See
Northern Ireland,
Lebanon,
Palestine, etc.
So the nature of your
fight does not depend on
what you fight for; it depends on
how you fight for it.
The thin red line between
Terrorism and
Resistance has a simple name : it is called
innocent civilians. The minute you intentionally
kill civilians in order to reach your
goals, whatever they are, you become a
terrorist.
It's as simple as that.
This is the most commonly used
definition (and in fact the only one) for
terrorism in
international diplomacy.
Note that this is not a
permanent doom: being a
terrorist at some time does not prevent you from promoting
peace later on. See
Yasser Arafat (Peace
Nobel Prize winner).
Note also that from this
viewpoint,
XXth century wars amount to little more than State-sponsored terrorism - although the
scale usually differs.