The major driver of cost is flight time for warplanes and steaming time for ships — not missiles or bombs, said Richard Aboulafia, a military aviation analyst with the Teal Group. A warplane can cost at least $10,000 per hour to fly. "What clobbered us over the past decade wasn't procurement (of weapons)," Aboulafia said. "It was operations and maintenance."

Pentagon contractors have been responding to the pullback in U.S. military budgets by shifting focus to international markets, said Philip Finnegan, director of corporate analysis at Teal Group, a Fairfax, Virginia-based consultant that tracks defense and aerospace companies.

Even with revenue at Lockheed, Raytheon, General Dynamics and Falls Church, Virginia-based Northrop down 4 percent since 2011, non-U.S. sales have climbed 9 percent during that stretch. The four companies also have pared expenses, including reducing their combined workforce since 2011 by 23,000 people, or about 6 percent, according to data compiled by Bloomberg.

The improvements to profitability, combined with investor-friendly moves such as stock buybacks, may influence share prices more than the strife in Iraq and Syria, Finnegan said.

"Clearly the world has become increasingly unstable. The question of whether that has a major impact on the defense budget is uncertain," Finnegan said. "There may be an investor psychology that suggests that there's going to be a large benefit to these companies. But the jury is still out."

Phil Finnegan, an aviation analyst with the Teal Group, said while the U.S. has led the world in developing the technology behind drones, it's fallen far behind when it comes to letting them fly legally.

"Countries like Canada, Australia, the United Kingdom — a lot of European countries — are going after this market," he says.

It'll take the FAA several years to finalize regulations for all drones, Finnegan says, but he believes this initial move will make the American motion picture industry more competitive on the world stage.

"You don't use Tomahawks against small moving targets, only fixed buildings, or possibly ships," said Steve Zaloga, a missile expert for Teal Group, a Virginia-based military and aviation analysis firm. "I think more broadly, the Tomahawk has typically been used where you don't want to lose any aircraft, so you'd send it into areas with enemy air defense or that is deep behind enemy lines."

Analyst Richard Aboulafia of the Teal Group interpreted the Marine Corps' comment as putting pressure on Rolls. "When you're in a sole-source situation and you're not happy with the price of spares and durability of spares, the best way to put pressure on the contractor is to imply that there could be competition in the future," Aboulafia said. "If [Rolls] could somehow combine lower cost with higher performance, that might be something [the Marine Corps] would really want, but on the other hand, it's not clear that's what's going on here."