Readers interested in a wider range of feedback on Gerson's editorial may want to read comments in response to his original Washington Post article which includes a 4:38 video discussion of related topics and, toward its end, a chart of religious voters' exit poll survey results. 

Those with more time may want to consider some books I've read, listed by year of publication. Time periods matter, e.g. Falwell changed his mind on political activism between MLK and Reagan. Also Gerson worked with David Kuo in the White House under Bush 43. Be advised, these books take issue with political activism by "the Church."

Wood, James E. Jr. NATIONHOOD and the KINGDOM. 1977.
Thomas, Cal and Ed Dobson. Blinded By Might, Why The Religious Right Can’t Save America. 2nd ed.  2000.
MacArthur, John. Can God Bless America? The Biblical Pathway to Blessing. 2002.
Kuo, David. Tempting Faith, An Inside Story of Political Seduction. 2006.

For my views, search Juneau Empire for past "My Turn" editorials.