A launch basket is a military term involving ground-launched rockets or missiles. For a particular target or target area and a particular type of rocket or missile, it is fairly simple to determine set of points from which the rocket or missile must be launched in order to reach the target. That is, if you want to hit a particular place, you need to launch the rocket from within the bounds of a particular area. The boundaries can be imposed by physics, by politics, or by strategy/tactics, but the potential launch area is known as the 'launch basket.'

To use a particularly timely example, Hamas forces in the Gaza Strip wishing to hit effective Israeli targets (which are all to the north and east) with the rockets available to them are limited to launching from an area in the northeast corner of the Gaza Strip itself. The southern and western borders of this area are defined (roughly) by the range of their rockets and the Mediterranean Sea respectively, and the north and east bounds are defined by the state of Israel's border - and hence the area of its effective peacetime control. One of the goals of the current Israeli military operation (Operation Cast Lead?) is to secure the area of the launch basket in order to apprehend any rocketeers and prevent further launches.