President Obama's pick to lead U.S. forces in Afghanistan warned Tuesday that more casualties will come before the war is over -- and that a obtaining U.S. victory in the region will be an uphill battle.
"Success will not be quick or easy. Casualties will likely increase. We will make mistakes," Fox News reported McChrystal said at his confirmation hearing before the Senate Armed Services Committee.
But, he said, "We must succeed."
McChrystal said that winning the war in Afghanistan is critical to national security -- and that he could help lead U.S. forces to a victory.
The former head of the Joint Special Operations Command, McChrystal is known for his covert special ops tactics and could be a drastic change from Gen. David McKiernan's traditional, classic command.
More than 68,000 troops will be in Afghanistan by the end of the year -- a number some have speculated is still too small.
Sen. John McCain, the ranking Republican on the committee, said the troop number should be bolstered to 200,000, more than double its current size.
More than 60 American troops have died in Afghanistan this year.