Four years into the Obama administration's high-priority U.S. exports push and the U.S. aerospace and defense industry's earnest efforts to expand sales internationally, new data show moderate success as well as major warning signs.

According to widely regarded analysis from a Swedish defense think tank comparing defense exports in 2009-13 and 2004-08, the U.S. remains the world leader and grew its output 11% between the two five-year periods, which mark the White House handover from George W. Bush to Barack Obama.

But Russia is gaining market share, and in one measure the former Cold War adversary has become the towering leader in selling weapons to the largest import market, India, according to the Stockholm International Peace Research Institute (Sipri). A Chinese export surge, meanwhile, has vaulted it ahead of France and the U.K.

Sipri says the five largest suppliers of arms, gifts and production under license in 2009-13 were the U.S. with 29% of total, Russia (27%), Germany (7%), China (6%) and France (5%). In 2004-8, the U.S. supplied 30%, Russia 24%, and China just 2%. Sipri says five-year stretches are best for comparison because they smooth out annual aberrations and allow time for announcements to prove true or not.

Russian exports grew 28% between the 2004-08 and 2009-13 periods, and in the latter timeframe Moscow became the largest exporter of warships worldwide—supplying 27% of the total, including an aircraft carrier to India—and claimed 75% of total Indian arms imports. In contrast, the U.S. accounted for 7% of Indian imports in 2009-13, marking “the first time [America] became the second-largest arms supplier to India,” Sipri states.

“Russia has maintained high levels of arms exports despite the crisis in its arms industry in the post-Cold War period,” says Sipri's senior researcher Siemon Wezeman. Moscow delivered arms to 52 nations, but India, China and Algeria together took in more than half of Russian exports. Aircraft made up 43% of Russian exports, including 219 combat airplanes in 2009-13.

China, meanwhile, surpassed France and grew 212% between the two time periods. Sipri says China supplied major arms to 35 states in 2009-13, mainly “low- and middle-income” countries. In fact, almost three-quarters of Chinese exports went to Pakistan, Bangladesh and Myanmar. But NATO member Turkey's initial selection last year of China's HQ-9/FD-2000 surface-to-air missile system over Western and Russian alternatives—a choice some observers believe could still be reversed—proved noteworthy.

Indeed, the surge of Russian and Chinese exports underscores a deepening concern in the Pentagon about not only the high-technology capabilities of those countries, but also the potential to run into their hardware elsewhere in the world. “One of the concerns about China is not just that they are modernizing—we don't anticipate a conflict with China, certainly—but [that] they export,” Pentagon acquisition czar Frank Kendall told Congress in January. “And the weapons systems they develop we would face potentially with other people.”

What's more, Chinese advances in surveillance, hypersonic weapons and air defenses could alter current funding plans for major U.S. weapons programs, and even their export potential, notes Capital Alpha Partners analyst Byron Callan. “It may take several more years for these advances to result in credible systems that could be fielded,” he says of China. In contrast, U.S. major defense acquisitions traditionally take decades. “China should be in a position to export these, too, and that will influence international demand,” Callan says.

Along those lines, Sipri analysts say it is apparent that both China and the U.S. are using arms exports for foreign influence, particularly in the Asia-Pacific region. Overall, the flow of arms to Africa, Latin America and Asia and Oceania increased “significantly” between the two time periods, while there was a “notable” decrease to Europe. Arms transfers to the Middle East remained essentially unchanged, Sipri says.

Still, the latest data reflects the Obama administration's 2010 effort to double total U.S. exports and streamline export licensing, as well as to use military sales as a key tool in the 2012 strategic “pivot” to Asia-Pacific following the post-9/11 wars. Leading and mid-tier U.S. defense contractors also have made a pronounced effort to seek more international sales since the last recession and subsequent depression in Pentagon spending. In 2009-13, aircraft represented 61% of U.S. exports, including 252 combat aircraft, Sipri shows.

Nevertheless, Sipri's analysis adds data to anecdotal evidence shared by U.S. officials and companies in recent years about the challenges they face in selling more abroad. Andrew Shapiro, the longest-serving assistant secretary of state for political-military affairs until his retirement last April, told Wall Street investors in February that countries are looking for other providers and do not want to be “too beholden” to the U.S.

U.S. technology tends to be the most capable and most expensive, he says, which is not what foreign customers always want. “For many of our partners, the high-end systems are unaffordable,” Shapiro says. “Particularly for countries facing counterinsurgency, counterterrorism types of issues, you don't need the most sophisticated fighter.” To U.S. companies looking to boost the bottom line with exports he notes: “You need to build in more risk, and you need to be diversified.”