Washington: Defence Secretary Robert Gates says that even winning the conflicts in Iraq and Afghanistan will not end the "Long War" against violent extremism and that the fight against Al Qaida and other terrorists should be the nation's top military priority over coming decades, according to a new national defence strategy he approved last month.

The strategy document, which has not been released, calls for the military to master "irregular" warfare rather than concentrating on conventional conflicts against other nations.

The strategy is a culmination of Gates' work since he took over the Pentagon in late 2006 and spells out his view that the nation must harness both military assets and "soft power" to defeat a complex, transnational foe.

"Iraq and Afghanistan remain the central fronts in the struggle, but we cannot lose sight of the implications of fighting a long-term, episodic, multi-front, and multi-dimensional conflict more complex and diverse than the Cold War confrontation with communism," according to the 23-page document, provided by InsideDefense.com, a defence industry news service.

"Success in Iraq and Afghanistan is crucial to winning this conflict, but it alone will not bring victory."

Gates embraces the "Long War" term that his predecessor, Donald Rumsfeld, invoked to equate the fight against terrorism with struggles against Soviet communism and Nazi fascism.

However, his strategy departs from Rumsfeld's focus on preemptive military action and instead encourages current and future US leaders to work with other countries to eliminate the conditions that foster extremism.

The document says that "arguably the most important military component of the struggle against violent extremists is not the fighting we do ourselves, but how well we help prepare our partners to defend and govern themselves."