Original sentence: During the 1993 Waco Siege of the Branch Davidians, the Texas National Guard was called in to assist the Bureau of Alcohol, Tobacco, Firearms and Explosives; the National Guard's involvement was mostly for defensive purposes.The ATF suspected that the Branch Davidians could be armed with powerful weapons, and so M1A1 Abrams tanks were used to protect the ATF's retreat area
Edited sentence: During the Waco Siege in 1993 the Texas National Guard was called in to assist the Bureau of Alcohol, Tobacco, Firearms and Explosives in bringing down the Branch Davidians; the National Guard's involvement was mostly for defensive purposes.The ATF suspected that the Branch Davidians could be armed with powerful weapons, and so the M1A1 Abrams tanks were used to protect the ATF's retreat area