IRAN'S STRATEGY FOR IRAQ

"... A successful US withdrawal from Iraq would free up military resources and restore US political will to focus on Iran. On the other hand, a hopelessly deteriorating quagmire in Iraq may force to US to seek an alternative path to victory by widening the war with an attack on Iran, or instigate an internal coup by supporting Iranian dissident groups. Thus Iran's strategy for Iraq is neither US withdrawal nor escalation, just a slow bleed to drive home the awareness of superpower impotency to the whole world..."
http://www.atimes.com/atimes/Middle_East/IC21Ak06.html