Getting something high is comparatively easy, getting something fast enough to orbit is a lot harder. Ballistic missiles follow a ballistic trajectory, there's

Getting something high is comparatively easy, getting something fast enough to orbit is a lot harder. Ballistic missiles follow a ballistic trajectory, there's a high initial impulse and then gravity takes over. Generally, you want the most efficient ballistic trajectory because every kg you save in fuel is 1 more kg for the warhead.