It is time for Germany to step out of the shadow of its Nazi past and take its share of responsibility for international security.

With an assertive Russia flexing its muscles to the east, Islamist terrorism bringing death to Europe’s streets, a U.S. president questioning America’s commitment to NATO, and Britain turning its back on the EU, Berlin must bite the bullet and acknowledge the need for a stronger German military.

The biggest constraints in doing so are not financial or material. They’re political and psychological. Germans can afford to spend more on defense but many of them don’t want it. Three generations after Hitler’s armies wreaked terror across Europe, Germans have gained too much economic and political power to continue hiding behind their understandable aversion to all things military.

Germany’s leadership has already gotten the message. Since Donald Trump’s election, Chancellor Angela Merkel has acknowledged that Europe cannot rely to the same extent on the United States and must instead take its fate into its own hands. As she starts coalition negotiations with the liberal Free Democrats and the Greens, responding to French President Emmanuel Macron’s challenge to build a European intervention force with a common defense budget and a common strategic doctrine should be high on the agenda.

Alarming proportions of German warplanes and helicopters can’t fly, and navy ships don’t sail for lack of maintenance, spare parts and technicians.

NATO, backed by U.S. nuclear weapons, remains best placed to deter Russian power in the east, but the European Union needs its own capacity to counter multiple security threats in the south. France is doing the “dirty work” of fighting Jihadist groups from Mauritania to Chad, mostly alone, while Italy's military has been crucial to coping with arrivals of boat people in the Mediterranean.

German defense spending has turned a corner since Russia’s 2014 seizure of Crimea and destabilization of eastern Ukraine prompted Merkel to lead the push for Western sanctions on Moscow. But at 1.22 percent of GDP, even after an 8 percent increase this year, it remains far below the agreed NATO guideline of 2 percent which Berlin has promised to approach by 2024. If spending remains on its current trajectory, there’s no chance the gap will be closed.

A quarter-century of attrition has hollowed out the armed forces. Alarming proportions of German warplanes and helicopters can’t fly, and navy ships don’t sail for lack of maintenance, spare parts and technicians. The Bundeswehr — the German armed forces — has shrunk from 500,000 at the end of the Cold War to fewer than 177,000 soldiers. It has to cannibalize old equipment to keep about 3,000 of them on international duty with the United Nations, NATO and the EU. Training and exercises have suffered from continuous cuts.

Re-equipping the Bundeswehr will take up to 15 years and cost an estimated 130 billion euros.

Europe’s biggest economy has long been the Continent’s weakest link when it comes to military resolve. Opinion polls show Germans support the Bundeswehr’s participation in a dozen international missions, including stabilization and training operations in Afghanistan, Northern Iraq and Mali and a frontline NATO deterrence role in Latvia, but they strongly oppose combat missions. Many don’t think Germany should even come to the defense of a NATO ally attacked by Russia.

Former NATO secretary-general Jaap de Hoop Scheffer says he had to plead with the chancellor in 2005 to send German reinforcements to the NATO-led stabilization force in Afghanistan, under fire from the Taliban. And even then, she refused to send them to the most dangerous areas. “Merkel told me: ‘You have to understand, we have the Bundeswehr, but the Bundeswehr is not there to fight,’” he told me in an interview.

Germans are right to criticize Western interventions in Iraq and Libya for having focused on short-term military success and neglected the disastrous aftermath. They are right to advocate a comprehensive approach to security problems including conflict prevention, development assistance, institution-building and empowerment of local security forces. But they are wrong to wrap themselves in a moral comfort blanket, parroting “there is no military solution” in all situations. Too often, that has been an excuse for free-riding.

The next government faces crucial choices on how and where to spend additional defense resources. NATO wants it to focus on building up heavy tank divisions to support Eastern allies to counter a possible Russian threat.

This fits most easily into Germany’s legal and political comfort zone but it may address the least likely contingency. France instead wants Berlin to develop light, rapidly deployable forces, airlift and refueling capabilities for more probable expeditionary operations on Europe’s southern periphery. And EU officials are keen for the Germans to prioritize cybersecurity, as well as police and administrative capabilities for conflict prevention and post-conflict stabilization.

If Germany is genuinely worried that a surge in its defense spending could scare its neighbors, it should put some of its extra resources into the planned European Defense Fund for military research and joint arms procurement, to help EU partners get more bang for their euros. No European nation can afford to develop the next generation of weaponry alone. Armaments cooperation, military specialization and integration of European forces are the way forward and are compatible with NATO.

EU defense cooperation has disappointed for so long that it’s easy to be skeptical now, but the stars have never been better aligned to achieve real progress.

Berlin also needs to adapt its institutional set-up to make itself a more effective partner, better able to exercise shared leadership in security and defense. Its strict parliamentary control over the military, highly politicized application of arms export restrictions, rigid annual budgeting and reticent strategic culture are all impediments to European cooperation. But these can all be fixed — given the political will.

Working closely with France — and including Italy, Spain and Poland wherever possible — will be crucial to building a more integrated European defense industry and military capabilities. Berlin and Paris should also try to include Britain, which has Europe’s biggest defense budget, through pragmatic arrangements once it leaves the EU. The U.K. should not be shut out of joint procurement or access to the European Defense Fund.

EU defense cooperation has disappointed for so long that it’s easy to be skeptical now, but the stars have never been better aligned to achieve real progress — but that will only happen if Germany steps up to the plate.

Paul Taylor, is contributing editor at POLITICO, the author of the Europe At Large column, and a senior fellow at Friends of Europe. His latest report for the think-tank: is "Jumping over its shadow: Germany and the future of European defense."