Unless we Europeans take our security seriously, North Americans will rightly ask why they should. Unless we recommit to our own defense, we risk seeing America disengage — and Europe and America drift apart. – NATO Secretary General Anders Fogh Rasmussen

BRUSSELS — NATO called on European Union leaders Thursday to work on improving their defense cooperation in the face of dwindling military budgets or face American disengagement.

British Prime Minister David Cameron came straight from World War I's battlefields in western Belgium to tell a summit of the 28 EU leaders to stand together to meet new defense challenges, even as he rejected pooling resources under a common EU flag.

At the same time, French President Francois Hollande used his country's military actions in the Central African Republic to underscore the need for common EU funding to back up the costly military operations of a single member state.

Despite those differences, Cameron said "we are making good progress" on closer alignment at the summit.

Still, NATO Secretary General Anders Fogh Rasmussen told the leaders to move swiftly since the United States might be inclined to weaken its military relationship, which dates back almost a century to World War I.

"Unless we Europeans take our security seriously, North Americans will rightly ask why they should," Rasmussen said. "Unless we recommit to our own defense, we risk seeing America disengage — and Europe and America drift apart."

For decades, NATO member states have paid lip service to joint projects and closer cooperation of their defense industries, but in the high-technology and high-investment age of drone incursions and cyber warfare, the EU still struggles to find synergies between its member states.

"We allow ourselves the luxury of maintaining 16 large shipyards which build warships — the USA has two," EU parliament President Martin Schulz told the leaders during the opening session of their two-day summit.

"We have 19 different types of armored personnel carrier and 14 types of battle tanks — the USA has one of each," Schulz said.

Hollande acknowledged that it was a key point the EU needed to address.

"Today we want to have a certain number of results, especially on the defense industry, which has to increase its cooperation on equipment," he said.

France has always been at the heart of drawing the EU nations together into an ever-closer union, so it came as little surprise that Hollande, faced with the mounting cost of military action in Africa, sought troop, equipment and financial input from partner nations.

"I have received a lot of support from European governments, from almost all of them. So financing also has to follow that political support," Hollande said.

Britain, ever wary when it comes to closer integration, sought to draw a line on how far European military cooperation should go.

Cooperation, yes, said Cameron, but "it is not right for the EU to have capabilities, armies, air forces and the rest of it and we need to get that demarcation correct."

Failing to get that balance right has cost the EU in duplication even as defense budgets suffer from the economic crisis.

"In 2001, the EU member states were still spending 251 billion euros ($343 billion) on defense, whereas in 2012 the corresponding figure was 190 billion euros ($260 billion)," Schulz told the EU leaders.

"In many cases, we would be quite incapable of carrying out a military operation without the support of the United States," Schulz said.

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