Carrier aircraft are built for repeated controlled crashes

What modifications keep an aircraft serviceable after repeated carrier landings?

The whole aircraft must be designed with much greater structural strength and shock absorption, not merely reinforced at one point.

A carrier landing is a controlled crash. The airframe, landing gear, shock absorbers, and supporting structure must repeatedly absorb loads that ordinary land operations do not impose in the same way. Reinforcing a few struts is only the beginning because the demand affects the aircraft as a system. A later reading from Ed Heinemann supplies the engineering detail behind this short explanation. Together they state the basic naval-aircraft design problem.