Resolution in Iraq?

[relativity_x]

I'm interested in the negatives of pulling out of Iraq over the next year?

The US wants to ensure that that poitical, economic, and security issues are all resolved before withdrawing troops. How do they plan to do that? Is this ambition even possible considering the polarity between the Sunni/Shi'a ideologies?

Since Al Qaeda and other insurgents are figthing US troops, wouldn't violence subside if the US troops pulled out?

Also, why does the US believe that either the Shi'a Sunnis/Kurds can wipe each other out? Neither of the groups have air attack/nuclear weapons that they can use.

Since it's been two years since we've installed a government/military in Iraq, isn't it time for them to fight for themselves? Why is securing the Oil, so important that we want to continue policing the civil war between the Sunnis/Shi'a?

I'm sorry for all of the questions, but I have yet to make up my mind about staying/withdrawing from Iraq. I believe these questions will allow me to make a decision if the US can justify staying in Iraq.