This was probably done on purpose so Obama can have a Marilyn Monroe moment to compare him to JFK.
Check it out:

President Barack Obama saved wife Michelle’s skirt from blowing above her head in the wind as they boarded Air Force One today.

As the Obamas boarded the plane in Houston, Michelle’s skirt began to vigorously billow in the wind. Barack kindly placed his hand over his wife’s bottom to save her from potentially embarrassing photos.

In doing so, the President helped Michelle avoid a fiasco similar to the ‘Marilyn moment’ experienced by the Duchess of Cambridge on Monday when she disembarked her flight in Wellington, New Zealand.

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