Although the consensus is that Tomahawks are a highly successful weapon, these weapons have several limitations. One of these is that their flight paths are relatively predictable, which is a function of the fact that some terrain, notably deserts, provides relatively few features for terrain following guidance. A second problem is that mission planning for terrain following guidance systems is more time consuming and complicated in terms of intelligence requirements than one might expect. For example, to use Tomahawks a unit would have to request a targeting package from such agencies as the Defense Mapping Agency to gather the data necessary for a mission. A third limitation was that Tomahawks could not be used against hardened targets because the 1,000 pound warhead, the weapon's accuracy, and its final kinetic energy when it hits the target do not produce high probabilities of kill. The final limitation was that Tomahawk cruise missiles cannot attack moving targets because they are guided to a position rather than to a specific target. Similarly, a Tomahawk cruise missile could not attack relocatable, that is mobile, targets because these may move while the mission is being planned or during the flight of the cruise missile.