alternatehistory.com

So that's the challenge, keep the war going [or in a stop-start pattern] for 13 or more years.

Lesser challenge: Keep the Bosnia war [lasted 92-95 in OTL] going as long as the Syrian Civil War. [5 years & 8 months]

Alternate challenges:

Make post-2003 Iraqi sectarian strife end its violent phase or the Syrian civil war end its violent phase in under 4 years.
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