It can hit cities and towns. Even the impact of a medium-sized meteor would start earthquakes and kill people NEO's could cause much damage on land. There are a few ways to prevent an asteroid impact. The method that sounds most reasonable to us is to attach solar sails to the asteroid. You can use solar sails to collect solar wind and actually move the asteroids.
Solar wind is the flow of matter, it is the energy the sun throws out into space.
The solar wind creates a continuous current so you would not need fuel as in a rocket. The sails are planned to be super huge as in 7 hundred km wide. Read more on solar sails. Even though the U.S already has a few monitoring stations, we still feel another one would really help us find and protect ourselves from asteriods more effectively. We know of 2 NEO monitoring stations, one called the Minor Planet Center and the other one called NEAT .