Whether Hobbs Act robbery qualifies as a crime of violence for purposes of 18 U.S.C. 924(c)

QUESTION PRESENTED I. Whether Hobbs Act robbery qualifies as a crime of violence for purposes of 18 U.S.C. 924(c), since the elements of Hobbs Act robbery, especially attempted Hobbs Act robbery, which may be completed through an attempted threat alone, fall outside of the definition of a crime of violence necessary for conviction under 18 U.S.C. 924(c)? 1