WASHINGTON (AP) — The United States and its partners have shortchanged Afghanistan by focusing on short-term goals pursued without a cohesive strategy or a clear understanding of the way the poor, decentralized country works, an independent study concludes.

The incoming Obama administration should refocus the U.S. war and rebuilding effort in Afghanistan and think of the project as the work of at least a decade, according to the report compiled by the United States Institute of Peace.

The assessment was set for release Thursday at a conference to be attended by Joint Chiefs of Staff Chairman Adm. Mike Mullen and Army Gen. David Petraeus, who is in charge of the Afghan and Iraq wars.

Petraeus’ own review of U.S. strategy in Afghanistan is expected to be presented to Obama the week after he takes office Jan. 20. The plan would shift the focus from the waning fight in Iraq to the escalating Afghan battle.

President George W. Bush’s in-house Iraq and Afghanistan adviser has already done a separate assessment; it has not been made public.