US Secretary of State Mike Pompeo warned of the dangers posed by Russia and China and urged NATO to raise and confront "today's challenge."
When he visited Berlin, Pompeo said that the method China used to suppress its own people would be "terribly familiar" to East Germans.
And Russia accused of invading neighboring countries and breaking opposition.
He recently mocked the remarks of French President Emmanuel Macron, who NATO said "brained."
But Pompeo told reporters: "For decades … to grow and change. To face today's reality and today's challenges.
"If countries believe they can get security benefits without providing NATO with the resources they need, there is a risk that NATO will be ineffective or useless if it doesn't live up to its promise."
President Donald Trump has accused NATO members of Europe not providing a fair share of military spending and rely too much on US defense.
NATO celebrates its 70th anniversary at the summit in London next month.
What did Pompeo say?
He was speaking in Berlin the 30th anniversary of the fall of the Berlin Wall.
Commenting on the incident, Pompeo said, "Western – we all got lost in the aftermath of that proud moment."
"We have to defend what was so hard in 1989," he said. "We must recognize that we are in value competition with countries that are not free."
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"We thought we could get our resources away from allies and armies. We were wrong," he said.
"Today led by a former KGB officer stationed once in Russia-Dresden [President Vladimir Putin] -Invade neighbors and kill political opponents. "
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The relationship between Washington and Moscow has plummeted since 2014, when Russia merged with the Crimean peninsula of nearby Ukraine.
The alliance became even more tense when US intelligence officials concluded that the Kremlin interfered in the 2016 presidential election.
Nevertheless, Trump and Putin are doing a good job personally. On Friday, President Trump was invited by a Russian leader to consider attending a Victory Day event in Moscow next May.
Pompeo accused the Chinese Communist Party of "forming a new authoritarian vision," and warned the German government about building a fifth-generation data network (5G) using China's telecommunications giant Huawei.
Chinese Foreign Ministry spokesman S huang (Geng Shuang) responded brilliantly and accused Pompeo of ideological prejudice and Cold War thinking.
"The attempt to separate the Chinese from the Chinese Communist Party is a provocation for the whole Chinese and destined to fail," he said.
What did Macron say?
In an interview with the Economist, the French president said that the main guarantor, the United States, keeps its promise to its allies.
He warned European members that they could no longer defend their alliance established to reinforce Western and North American security at the beginning of the Cold War, relying on the United States.
He recently mentioned that Washington had not consulted with NATO before withdrawing troops from northern Syria.
Prime Minister Macron also questioned whether NATO was still committed to collective defense.
On Thursday, German Prime Minister Angela Merkel, the key ally, said he did not agree with President Macron's "pole word."
She admitted that there was a problem while visiting the Secretary General of Jens Stoltenberg Nato in Berlin, but admitted that there was a problem, "I don't think this decision is necessary."
But Russian Foreign Ministry spokesman Maria Zakharova said that Macron had "an accurate description of the current state of NATO."
She posted on Facebook: “True words and words that can solve the problem”