Cadre

Military. the key group of officers and enlisted personnel necessary to establish and train a new military unit.
a group of trained or otherwise qualified personnel capable of forming, training, or leading an expanded organization, as a religious or political faction, or a skilled work force:
They hoped to form a cadre of veteran party members.
(especially in Communist countries) a cell of trained and devoted workers.
a member of a cadre; a person qualified to serve in a cadre.
a framework, outline, or scheme.
Contemporary Examples

The Next Fort Hood Ken Allard November 9, 2009
Egypt’s Tahrir Activists Weigh Abandoning Street Protests For Runoff Vote Alastair Beach May 31, 2012
Processing the Murder of Eric Ohena Lembembe Neela Ghoshal July 16, 2013
Archie Comics: Corporate Brawl Over-Sexual Harassment Charges Nancy Hass February 1, 2012
A Socialite’s Revenge Jacob Bernstein March 8, 2010

Historical Examples

Integration of the Armed Forces, 1940-1965 Morris J. MacGregor, Jr.
The Political Future of India Lajpat Rai
McClure’s Magazine, Vol. XXXI, No. 6, October, 1908 Various
The Seventh Manchesters S. J. Wilson
Italian Highways and Byways from a Motor Car Francis Miltoun

noun
the nucleus of trained professional servicemen forming the basis for the training of new units or other military expansion
a basic unit or structure, esp of specialists or experts; nucleus; core
a group of revolutionaries or other political activists, esp when taking part in military or terrorist activities
a member of a cadre
n.
cadre [(kad-ree, kah-dray)]