Puerto Rico
defense is the responsibility of the US

Saint Helena
defense is the responsibility of the UK

Saint Pierre and Miquelon
defense is the responsibility of France

Samoa
Samoa has no formal defense structure or regular armed forces;
informal defense ties exist with NZ, which is required to consider
any Samoan request for assistance under the 1962 Treaty of Friendship

San Marino
defense is the responsibility of Italy

Sao Tome and Principe
Sao Tome and Principe's army is a tiny force
with almost no resources at its disposal and would be wholly
ineffective operating unilaterally; infantry equipment is considered
simple to operate and maintain but may require refurbishment or
replacement after 25 years in tropical climates; poor pay and
conditions have been a problem in the past, as has alleged nepotism
in the promotion of officers, as reflected in the 1995 and 2003
coups; these issues are being addressed with foreign assistance as
initial steps towards the improvement of the army and its focus on
realistic security concerns; command is exercised from the
president, through the Minister of Defense, to the Chief of the
Armed Forces staff (2005)

South Africa
with the end of apartheid and the establishment of
majority rule, former military, black homelands forces, and
ex-opposition forces were integrated into the South African National
Defense Force (SANDF); as of 2003 the integration process was
considered complete

South Georgia and the South Sandwich Islands
defense is the
responsibility of the UK

Spratly Islands
Spratly Islands consist of more than 100 small
islands or reefs, of which about 45 are claimed and occupied by
China, Malaysia, the Philippines, Taiwan, and Vietnam

Svalbard
demilitarized by treaty on 9 February 1920