During the red scare of 1919-1920, led the attack on the alien threat. a. william jennings bryan b. a. mitchell palmer c. clarence darrow d. eugene debs e. warren g. harding

b. Mitchell palmer

Explanation:

The sequence of raids occuring were called the Palmer Raids. These raids were aimed at capturing the immigrants and deporting them out of the United States. Palmer, the Attorney General, was responsible to lead and carry on the raids.  World War I and Russian revolution resulted in fear and rejection for the immigrants in the US. This was named the Red Scare. This fear among the people of the US gave momentum to the Palmer raids. The immigrants and non-residents of the US were referred as aliens.  The US Labor Department was upset by these raids as this went against their authority to deport people.