China's splendid display of troops and weapons at its 70th anniversary celebration on Tuesday was "a military show of strength" amid economic challenges, one professor told CNBC.

"(China has) got a lot of problems, but today is the day that they want to show an image of great confidence, pride, and strength," professor at University of California San Diego, Susan Shirk, said Tuesday.

The celebrations, which boasted one of Beijing's largest military parades, took place as China faces economic and political challenges. Even as tens of thousands were celebrating National Day in China, demonstrators in the territory of Hong Kong marched through the streets in its 17th week of protests.

In Beijing, Chinese President Xi Jinping, addressed the nation and pledged that "No force can stop the Chinese people and the Chinese nation forging ahead."

The military parade, with all its pomp and pageantry, involved more than 15,000 military personnel who took part in celebrations commemorating the Chinese Communist Party's 70 years of rule.

On display were 160 aircraft and 580 pieces of military equipment, including drones and missiles. The Dongfeng 41, a nuclear-capable missile, was also unveiled during the military parade. The Associated Press quoted analysts as saying the weapon could reach the U.S. in 30 minutes.

"It looks like this is almost entirely, if not entirely, a military show of strength," Shirk told CNBC's Street Signs.