"This is the best cover shoot we've ever done," Kerry gushed.
Prior to the photo shoot, the actresses were given a tour of the White House. SJP wore Oscar de la Renta and heels from her own shoe line for the event, while Kerry and Mrs. Obama both wore Narciso Rodriguez.
One part you won't see on the Glamour cover is that Kerry and SJP had to stand on boxes just to get close to Mrs. Obama's height. The first lady is 5' 11" tall, while Kerry and SJP are 5' 4" and 5' 3", respectively.
The real reason for the visit was Mrs. Obama's Joining Forces initiative, which supports America's service women and military spouses.
"If I had the opportunity to serve as first lady I was going to use this platform to shine a light on their challenges and to be their voice," Mrs. Obama said. "And get America to rally around these people and to serve them as well as they've served us."
Glamour's Power Women issue hits newsstands April 14.