As you point out it must be conducted with strength, determination, and unyielding agression. In addition, and leaving out moral considerations, if the war in on foreign soil, it must be intelligently conceived and wisely prosecuted. There is small room for error, yet error happens in every war and error is pervasive in every war of long duration.

Wars that involve rebels, like your example, usually end with victory by one side or the other, but history has shown us over and over that we are not smart enough to get involved in wars where our goals are not clearly defined and our determination is questionable.

We can argue ad nauseum about the morallity of the Iraq war but whether it was justified or not, we mucked it up, and the bottom line is, it was a mistake. It was/is too long and way too costly.

Since WWII, Korea was a pragmatic success, based on the S Korean economy vs the hell in N Korea. Viet Nam was a fiasco based on a faulty premise. The Balkans thing was a success based on the limited scope and popular world support. GWI was a success due to popular support, task objective, and short duration. GWII was a bad idea, whether you see us as victors or losers. We had about a year to get it done and we have been there for 7 years. The cost has been too high on every level.

BTW, it remains to be seen whether of not the Sri Lanka rebels are laying down their weapons only to pick them up again at the first opportunity. Excuse my cynicism.