This is 100% PURE BULLSHIT. In fact, during the 2016 convention, Hillary supporters were CONSTANTLY breaking out into chants of "USA" - not least to drown out chants from the Bernie supporters.
The Democrats have been deliberately martial and bellicose, donning the mantle of patriotism and jingoistic passion ever since John Kerry started his acceptance speech in 2004 by saying, "I'm John Kerry and I'm reporting for duty."