As the NATO summit opens in Brussels, President Donald Trump is poised to scold countries for not paying the amount they agreed to on defense and is calling out Germany for making deals with Russia at the same time the EU expects the US to protect it from Russian aggression.
Just six of the 29 member countries pay the full 2 percent of their GDP on defense as agreed to under the NATO treaty.
In 2017, the US paid more to NATO than Germany, France, Italy, Spain and the UK combined, and President Trump has made the case the US is not the world's piggy bank.
For example, Canada is projected to spend just over 1.2 percent of its GDP on defense this year.
Prime Minister Justin Trudeau justifies that amount by pointing to Canadian investment in new military equipment and the prominent role the nation plays in NATO missions.
"Those sorts of tangible elements are at the heart of what NATO stands for," Trudeau said at a German Marshall Fund event taking place alongside the NATO summit.
"You can try and be a bean counter and look at exactly how much this and how much money that, but the fundamental question is – is what you're doing actually making a difference?" he added.
Despite the funding deficits, the 29-nation NATO alliance will use the two-day conference to demonstrate it remains capable of confronting Russia's aggression and continuing to fight terrorism.
They're also expected to renew their financial and personnel support for the Afghan army.
NATO has 16,000 military personnel helping train troops in Afghanistan, and British Prime Minister Theresa May says the UK will provide an additional 440 people.
"I think that shows when NATO calls, the UK is one of the first to step up," she told reporters.
In a show of NATO might to Russia, leaders are expected to approve a plan to deploy 30 battalions, 30 battleships and 30 air squadrons within 30 days of a crisis.
They're also approving two command headquarters – one in Norfolk, Virginia, and another in Ulm, Germany – to improve movement of troops and equipment across the Atlantic and through Europe.
NATO Secretary-General Jens Stoltenberg acknowledges the disagreement over funding between the US and other countries but is staying out the spat.
"A strong NATO is good for Europe and good for the United States. Two world wars and a Cold War taught us that we are stronger together than apart," he said.
Meanwhile, President Trump is singling out Germany for not paying its fair share on defense while dolling out hundreds of millions of dollars to Russia for energy.
Berlin has given its blessing for the building of the Nord Stream 2 pipeline that will bring gas to Germany by way of the Baltic Sea.
The president says it's "inappropriate" that the US is investing in European defense against Russia while Germany, the EU's largest economy, is working on major energy deals with Moscow.
"Germany is a captive of Russia," the president said.