In a large mixing bowl, beat cream cheese, butter, vanilla, and salt with an electric mixer on medium speed until light and fluffy. Gradually beat in powdered sugar until it reaches spreading consistency.
In a gallon size resealable plastic bag, toss cherries with 2 cups powdered sugar. Pour into a sieve and shake excess sugar off.
Transfer cake to serving platter or cake board, if desired*. Frost cake with all but ½ cup of the cream cheese frosting.
Outline the flag design in the frosting with a toothpick. Fill the top left corner of the cake with blueberries to represent the blue part of the American flag. Alternately place horizontal rows of raspberries and powdered sugar cherries across the remainder of the cake until the flag is finished. Transfer the reserved ½ cup of frosting into a piping bag fitted with a small closed star tip. Pipe stars on top of the blueberries.
*if you plan to transfer the cake on top a serving dish or cake board, be sure to line your baking pan with parchment before baking the cake