U.S. President Donald Trump is facing renewed scrutiny after a viral video showed him walking across the tarmac before boarding Marine One in North Dakota. Critics claimed the president appeared unsteady, while the White House dismissed the speculation and defended Trump's 'perfect walk'. The footage was captured during Trump's visit to the Theodore Roosevelt Presidential Library following his arrival aboard the Qatar-gifted Boeing 747 serving as a temporary Air Force One. Here's why the video is spreading online and how the White House responded.