President Biden's speech rallying NATO members was all show since those nations don't provide enough military funding to defend each other, according to a national security adviser to former President Trump.

"If you're not putting 2% of your GDP into defense, then some of your systems may not be able to fight in defense of the alliance when called upon," retired Lt. Gen. Keith Kellogg. told Fox News. 

In a Wednesday address to a group of eastern European nations, Biden stressed the importance of a strong and unified NATO. The message came soon after Russian President Vladimir Putin announced that his nation would no longer participate in a nuclear treaty with the U.S., days ahead of the anniversary of its invasion of Ukraine.

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Putin "doubts our continued support of Ukraine. He doubts whether NATO can remain unified," Biden said in his speech from the Royal Castle in Warsaw. "But there should be no doubt, NATO will not be divided, and we will not tire."

"Article 5 is a sacred commitment the United States has made," Biden continued. "We will defend literally every inch of NATO."

Article 5 stipulates that an attack on any NATO member is treated as an attack on all, requiring a joint response.

"Everybody kind of understands what Article 5 is," Kellogg said. "An attack on one is an attack on all."

He said equally important is Article 3, which states that NATO countries must fund their defense well enough to defend themselves and the collective alliance against an attack. 

"They go hand in glove," he said. "They're both important. They both rely on each other."

In 2014, NATO allies met in Whales and pledged to try to increase defense spending to 2% of their GDP, and 20% of that amount on modernizing their equipment over the next decade in order to fulfill Article 3.

"Most of the countries didn't do that," Kellogg told Fox News. "So, they didn't really fulfill Article 3, which impacted on Article 5."

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Kellogg said Biden's message about a strong and unified NATO rings hollow since about 20 of the 30 allied countries are unprepared to fulfill a call for aid. He pointed to Germany, France, Spain and Italy as among the least prepared. 

"If you don't get to 2% GDP, you will not have the military structure, the military forces to be able to support the rest of the alliance as they enforce Article 5," Kellogg said. "They won't be able to do it because they don't have the forces."

"It's so important we continue to, from the bully pulpit, talk about NATO, talk about their unfunded military establishment," he added. "President Trump did it all the time, and they actually started to increase their defense budget." 

In addition to the U.S., which spends nearly 4% of its GDP on defense, the Baltic countries, Poland and Britain are the most prepared to act swiftly and effectively if Article 5 is invoked, Kellogg said. 

Despite Biden’s remarks that fueled speculation over whether NATO will get involved in the Russia-Ukraine conflict, Kellogg said he does not see that happening anytime soon. 

"It was a diversion because he hasn't come up with a plan to help end this war," Kellogg told Fox News. "I want to know what the policy is to end this war. How are you going to do it? Define that to the American people."

"Instead, he uses rhetoric and talks about Article 5 and NATO but it doesn't impact the fight at all," he said. "Russia's not going to go into NATO. They don't have the capacity to even get to the western part of Ukraine, let alone attack NATO, and they understand very well if Putin does that, it's the end of Russia." 

To watch the full interview with Kellogg, click here.