There are five types of territorial morphology - compact, prorupt, elongated, fragmented and perforated. Because the Philippines is an archipelago, it belongs to the "fragmented" group. A
blog post by map-enthusiast Frank Jacobs on Big Think creates the idea that the shape of a nation affects the set of problems it faces.
"Fragmented states often experience great centrifugal pressures, with
separatism affecting their outlying fragments. This is true of the
Philippines, the central government of which only last October concluded
a peace deal with the Moro Islamic Liberation Front,
which had waged a separatist guerilla on the southern island of
Mindanao. Something similar has been endemic in Aceh, at the western tip
of Sumatra, where both the Dutch colonisers and the Indonesian central
government have battled insurrections and rebellions.
Indonesia has had to contend with a few other centrifugal forces, one of
which actually succeeded (and seceded): East Timor, which in 2002
became the 21st century’s first independent state. In the process, East
Timor changed from being a fragment of a fragmented state to being the
solid core of a compact state."