Well if that's your conspiracy theory, then you should know that whatever a swat team were to change their uniform to, a terrorist group could still buy from uscav, rangerjoes, gallsinc, acuarmy, or any military outfitter.
You, personally, can buy any police uniform right now with a credit card. Any uniform. Whatever a swat team were to change their uniform to, any criminal group could still imitate.
Terrorists don't wear uniforms, that's why the Geneva convention doesn't apply to them. They don't carry their weapons openly, have an established command structure (they operate in cells) and they don't comply to "the norms of war", preferring gurrila tactics instead.