President Donald Trump said he was "watching" the event staged by China on the 80th anniversary of Japan's defeat in World War II and "understood the reason" it brought together the leaders of China, Russia and North Korea publicly for the first time.

"I thought it was very, very impressive," Trump said Sept. 3 during an event at the White House. "But I understood the reason they were doing it. And they were hoping I was watching, and I was watching. My relationship with all of them is very good. We're going to find out how good it is over the next week or two."

The massive show of force showcased China's advancing military might in front of 50,000 guests and spectators. China staged a large and highly choreographed military parade in Beijing's Tiananmen Square, unveiling a new long-range hypersonic missile, underwater drones and even robotic wolves.

China's Xi Jinping used a crowd-pleasing speech to highlight how the country's growing military and diplomatic clout represents an alternative to a US-led world under Trump's White House that has strained relations with allies and rivals alike.

Trump complained the United States was left out of the speech.

"President Xi is a friend of mine, but I thought that the United States should have been mentioned last night during that speech, because we helped China," Trump said Sept. 3.

Trump addressed Xi, Russia's Vladimir Putin and North Korea's Kim Jong Un in an earlier social media post that accused them of working to "conspire against The United States of America." He also said in the post that the United States should be acknowledged for "the massive amount of support and 'blood' that The United States of America gave to China in order to help it to secure its FREEDOM."

Japan invaded China in a conflict that ended after Japan was defeated − in large part by the United States − in World War II.

Trump had earlier told reporters he did not see the parade as a challenge to the United States.

Asked Sept. 3 if he was upset that he wasn't invited to the parade in Beijing, Trump said, "It wouldn't have been my place to be there."

Contributing: Joey Garrison, Francesca Chambers

This article originally appeared on USA TODAY: 'Very, very impressive'. Trump responds to giant military parade in China

Reporting by Zac Anderson and Kim Hjelmgaard, USA TODAY / USA TODAY

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