Our track record is dismal with regard to forces we finance and train.
South Vietnamese troops
The Afghan government troops
The Iraqi government troops
After years - a decade or more - of financing, training and support the above forces are incapable of meeting underfunded, undertrained and underarmed irregulars.
Given these results, maybe the key to winning the war on terror is for us to finance and train the opposition.
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The reason is that people will fight for what they believe.
If the armies we train and support don't believe in what we're doing, why should we?

Germany plans to send troops to Iraq to train Kurdish fighters
Move to help in the fight against Islamic State would break the military policy that Germany has followed since 1945

Germany is planning to send troops to Iraq in a break with the military policy it has followed since 1945 - and one that may even require the constitution to be changed.

Angela Merkel, the Chancellor, wants to send a contingent of German soldiers to northern Iraq to help train Kurdish forces fighting the Islamic State of Iraq and the Levant (Isil).

German troops have served with international forces in Afghanistan, Bosnia and elsewhere, but only under missions with a clear United Nations mandate or Nato leadership.

A few German military personnel are already in northern Iraq training Kurdish peshmerga fighters, but Mrs Merkel’s government wants to send more than 100 troops, according to Bild newspaper.

http://www.telegraph.co.uk/news/worldnews/europe/germany/11288179/Germany-plans-to-send-troops-to-Iraq-to-train-Kurdish-fighters.html