The Northeast Air Command (NEAC) was a group of people whose job was to keep an eye on what was happening in the air in the northeastern part of the world. They used airplanes and radars to make sure everything was safe and to protect people from bad things like enemy planes or bad weather.
Think of it like a big grown-up game of "I Spy." The NEAC team would look out for things they could see or hear from the air, like planes or missiles, and when they spotted something, they would let others know so they could take action to keep people safe.
The Northeast Air Command was formed after a big event called World War II when countries all over the world were fighting each other and trying to be the most powerful. People realized that they needed to keep an eye on the skies in case any bad things were going to happen again. So, they created the NEAC to keep everyone safe from up above the ground.