An optical element mount is effective in high G environments to protect brittle optical elements in which tensile stresses are generated on surface S2 without degrading optical performance. A flexible spacer formed of a relatively low-stiffness material supports an optical element having a tapered outer periphery in an optical seat having a complementary tapered surface. When the optical assembly is exposed to the high G environment, the inertial loading drives the optical element in the aft direction into the flexible spacer and seat. This puts the optical element into a plate bending condition thereby inducing tensile stress on S2 which is at least partially offset by a compressive stress caused by the reaction force normal to the tapered interface. The stresses, both compressive and tensile, placed on the optical element in the high G environment can be very large. In the absence of the tapered mount and flexible spacer, the tensile stress placed on S2 would likely fracture or shatter the brittle optical element. When the inertial loading is removed, the optical element returns to its initial unstressed position.