Of course it is true that the actual battle plan will depend on
the situation we actually encounter. However, since this is a
scenario, I am only quoting the most likely response that I think
the SAF would take. Any real response would probably be some
variation on it.
It is an open secret that SAF relies upon preemptive strike to
defend Singapore. If there is even the threat of war, we must strike
immediately to create the strategic depth we need to defend
Singapore. So, actually yes, we are a rather trigger-happy nation in a
manner of speaking. Once we announce that we feel that we have been
threatened with war, the other side has about three hours before
the 50k active duty NSmen and regulars begin their assault to
convince us that we should not attack. That is why Singapore has
been called a "doomsday machine" and why our neighbors make so much
noise about our military posture.
An attack on Riau would be costly and dilute our strength, but it
would unfortunately also be completely necessary. We cannot allow
the enemy to gain a foothold so close to the mainland. Standoff
weapons like MLRS (and maybe even ERBB artillery shells) can even
be launched from there directly into Singapore and it is an ideal
staging point for ambhibious invasion. I disagree that a Riau
invasion can be skipped.
In any protracted conflict against both Malaysia and Indonesia, we
will eventually lose if we are drawn into a war of attrition. That
is why my suggested response aims for a rapid diplomatic resolution
to the conflict. By conducting a limited military action, with
clearly defensive goals and minimizing civilian casualties, it is
easier to present our case that we are the victims. By quickly
taking and maintaining the initiative, we force the other parties
to the negotiating table from a position of strength.
You suggest annexing Malaysia. This would be a military victory,
but a total and devastating political defeat. That would kill
Singapore more surely than a nuclear attack. Such actions are
simply not acceptable any more. At the very least, we will become
an embargoed and impoverished pariah state and face decades of a
new Confrontasi against our neighbors. At the worst, we will face
an armed international coalition, with the US at its head. Take
your pick. I'd rather not. I do not even want to ask what you mean
by inducing a "rapid demographical change" in annexed
Malaysia.
In fact, the problem of "what do we do once we get there" is the
biggest problem the SAF faces. We can easily defeat our neighbors
militarily, but we have no follow-on option. We cannot hold their
land, especially in the face of a hostile populace. Remember that
every NS soldier out there means one less worker at home -- we
cannot fight protracted conflicts because of our force structure.
While decades of uneasy UN mediated peace is not ideal, it is
probably the best option, if combined with a heavily policed DMZ.
Our neighbors would accede to such a peace because the alternative
is far worse -- we can DESTROY them if we wanted to (though we
would destroy ourselves in the process -- doomsday machine again).
That is why even when we are crying for peace, we must also bay for
war.
The issue of war reparations after a war is always thorny. Is the
goal justice, or welfare? It might be just to drag out all the
responsible parties and have them shot, but it might lead to more
misunderstanding, hatred and eventually suffering. The reverse may
also be true. And do not be too quick in assuming that it would be
the other side that starts the conflict. It may be our side, or
neither side, or both sides, or even a third or fourth party.
Things are never that clear cut anyway. I won't try to cover this
issue since what kind of war reparations (or war trials) should be
sought after a conflict depends too strongly on the specifics of
the conflict.
The damage from any such conflict would be incalculable.
Fortunately, such a conflict is also very unlikely. All three sides
know how futile the Mexican standoff that would result would be,
and there is no advantage to any party to start a war.
Nevertheless, it is an interesting scenario from a geopolitical
standpoint.