"I will never rush the solemn decision of sending you into harm's way. I won't risk your lives unless it is absolutely necessary," Obama pledges to 3,000 marines, naval officers and their families who packed into an airplane hangar at the Naval Air Station here.
"And, if it is necessary, we will back you up to the hilt. Because you deserve the strategy, the clear mission, and the defined goals, as well as the equipment and support that you need to get the job done," Politico quoted him, as saying.
Obama also offered his condolences to the families and loved ones of the14 Americans - 11 soldiers and three civilians - who were killed in two helicopter crashes in Afghanistan on Monday, making it one of the deadliest days of the war.
"They were willing to risk their lives, in this case, to prevent Afghanistan from once again becoming a safe haven for al Qaeda and its extremist allies," he added.
Obama is expected to make a decision on a new war strategy in coming weeks. The president has signaled he could wait until after the war-torn country holds a presidential runoff election on Nov 7.