I believe the Representative's reasons for pulling the flag are legitimately different than mine; I also think that we've whitewashed the whole history of Slavery in this country but that's another story.
So here's my question: Would this be like flying the Nazi or Imperial Japanese flag over the WW II memorial and claiming it's just for "historical" purposes? I'd like to think that any WW II veteran would be incensed by that type of display.
A little background, if you've been to Gettysburg you'd notice differences in some of the monuments on the field. The Confederate ones especially on the areas of the first day's battle, which the Confederates carried, are metal since they were placed for the most part in the 20th century. Nearly all the Confederate markers on the battlefield were not placed until well after most Union soldiers had died and control of the fields passed from Union Veteran organizations to the National Park Service. Confederate soldiers would participate in some of the last gatherings of Civil War veterans but there was a long time when the presence of a Confederate soldier on that scared field wasn't welcome. In Philadelphia mobs broke windows of any prominent person who didn't drape their houses in black as Lincoln's body passed thought the city.
It's clear to me, at least, that there was little sympathy for the Confederates by Pennsylvanians and other people who supported the Union and they would, IMHO, be appalled that openly Confederate symbols would be displayed in one of the states that provided the largest number of soldiers to the Union armies.