i will try to translate the term "strategy" from the greek wikipedia, as the origin of the term strategy is Greek from the word "στρατηγική" and which is formed by the words "στρατος + ηγούμαι" in english "army + lead"
Strategy is the way of using the present means to achieve the national/political goals to support our national interests in case of present or future conflict. It is a science and art (it is based on experience and talent).
A more complete approach on strategy comprises on at least two axis: the current strategy, which is associated with visual, tangible and direct targets and the strategic planning, which is associated with wider (extensive) goals, who aren't discribed with details, based on the strategic vision and with a typical depth of 15 years.
This word, as also the ones related with it {eg. stratigos (in english General), in Greek στρατηγος}, comes etymologically from Ancient Greece and originally had a clearly military meaning. More specifically, strategy declared the science or the art of military command and the necessary planning to achieve the best result when handling the living and the non living resources to reach our goals.
Strategy, is not used only in the combat field but also in other cases (politics,economy,trade etc) so this term is widely used to declare:
The plan of a business or an organisation
The logic and the acts to be followed in games (eg chess,computer games etc)
The plan which is set to achieve a goal which is of a high level of diffculty (eg a political campaign)
I hope i didn't confuse you
the text i translated is in this link
http://el.wikipedia.org/wiki/Στρατηγική