Polling has shown a majority of voters are fine with the confederate flag and see it as a symbol of southern pride, believe it or not. Also, if Cruz does get attacked for supporting the confederate flag, Hillary should get attacked to for the 2008 confederate flag background 2008 president pins.
Of course none of those were created or endorsed by the campaign, this is the Cruz campaign.
It's a vile symbol of oppression and subjugation of people based on their race. It belongs in a museum. Also, the point that really irritates me as a history nerd, it's not the 'Confederate Flag' like it was the flag of the CSA, it's the battle flag of the Army of Northern Virginia... so even more a symbol of violence in the opposition to the abolition of slavery.
Personally, I think of the confederate flag as just a piece of cloth that makes southerners feel more southern so it really isn't an issue for me. I'm fine with putting it in a museum. I'm just saying that this isn't an exactly a poisonous position by the cruz campaign.
