They need hooks on the planes. Think of aircraft carrier landings with cables. Lay the cables on shallow ponds.
Put a tailhook on an aircraft that was not designed for arrested landings, and you'll rip the tail off if you attempt an arrested landing. That's assuming the weight/balance isn't so screwed up as to prevent flying ... This is why, for example, the US Navy doesn't use F-15s and F16s.
The F-4 "Phantom II" was originally designed as a Navy/Marine fighter, with a tailhook for arrested landings on carriers. When the USAF adopted the F-4 as well, they retained the tailhook. Were they planning to carry out arrested landings? No ... the tailhook is very heavy. Removing it would have irreparably screwed up the balance of the aircraft.
I tripped out when I saw hooks on F-16s. The guard unit switched to F-15s, but I haven’t looked close enough to see if they have hooks too. Probably do.