Rabbi Gary Moskowitz is a firm believer in Jewish self-defense. As the president of the Tzedek Task Force on Counter Terrorism, this martial artist master and retired New York City police officer wants synagogues on high alert this fall. “There’s an extremist Muslim threat that’s being posed, and we have learn how to protect ourselves,” he said yesterday after a brief a training exercise at the Anshe Sholom Center in Kew Gardens, Queens. “We can’t be spiritual if we’re dead.” Using rubber guns and special combat skills, Moskowitz and his team of volunteers demonstrated to Tablet how congregants at High Holiday services this year can take action against would-be attackers.