There are now almost 160,000 U.S. troops in Iraq. That's more than at any time since the war began.
The invasion force that toppled Saddam Hussein in 2003 was more than 10,000 troops smaller than the force in Iraq today.
Whatever happens over the remaining 18 months of the Bush presidency, one thing is clear: It will be up to the next president -- or presidents -- to figure a way out of Iraq.
In January, President Bush announced a new strategy for Iraq, including a "surge" of nearly 30,000 additional U.S. troops into the war zone.
The new plan was an abrupt departure from the strategy pursued under the leadership of former Defense Secretary Donald Rumsfeld and the outgoing commander in Iraq, Gen. George Casey.
Rumsfeld and Casey had pursued a strategy that centered on the training of Iraqi security forces and gradually reducing the number of U.S. troops in Iraq. The mantra of the old strategy: "As they stand up, we stand down."
Both Rumsfeld and Casey were skeptical about sending more U.S. troops, arguing it was time to force the Iraqis to take more responsibility, or as Rumsfeld put it, "We're going to have to take our hands off the bicycle seat."
The surge may have been announced in January, but it did not happen overnight. Moving thousands of additional soldiers and Marines into a war zone takes time. The surge wasn't even complete until the end of June.
Under the command of Gen. David Petraeus, this beefed-up force is fighting a counterinsurgency war, driving insurgents out of Baghdad, block by block, and then staying in those neighborhoods to ensure they remain secure. The idea is to protect the local population and, in the process, turn the general population against the insurgents.
Democrats almost universally opposed the president's new strategy, calling it an "escalation." Some Republicans agreed.
Many of these critics argued that Iraq is now in a civil war and that it is time to start getting American forces out of the country, leaving it up to the Iraqis to resolve their differences.
Even under the new strategy, however, the United States is eventually supposed to take that hand off the bicycle seat. The surge is supposed to reduce the violence long enough for Iraq's warring factions to resolve some of their differences.
As Defense Secretary Robert Gates put it: "We are buying them time for political reconciliation, and every day we buy them we buy with American blood."
There's certainly been a lot of American blood spilled in Iraq since the invasion of Iraq on March 20, 2003. At least 3,698 American troops have died in Iraq. Nearly 30,000 have been injured, including at least 859 amputees.
Petraeus, who has a Ph.D. in international relations from Princeton University, is considered the military's pre-eminent expert on counterinsurgency war.
He has often said that the average counterinsurgency war takes 10 years to fight. But Petraeus knows that he won't have that long to fight this war.
As public support for the war has eroded, momentum in Congress has grown for forcing a withdrawal of U.S. troops.
In May, Congress voted in favor of a timetable for withdrawing U.S. forces. The bill would have required a withdrawal to begin this year and set a goal of withdrawing all U.S. forces by March 2008.