Cruise missiles have been described as the "poor man's air force," as they are cheap to build, easy to maintain and capable of delivering conventional and mass destruction weapons. It is important to note that the five HY-2/CSSSC-3 Seersucker cruise missile launched against Kuwait by Iraq during the US-led war of Iraq in 2003, were not detected or intercepted by American and Kuwaiti Patriot Theater missile defense batteries and that Hezbollah used anti-ship cruise missiles (ASCMs) during the conflict in Lebanon in 2006.These incidents highlight the threat from cruise missiles and the inability of missile defences to intercept them.

Cruise missiles are guided missiles, which can be launched from ship or aircraft and serve as precision bombs. Cruise missiles are of two types: land attack cruise missiles (LACMs) and ASCMs. At present, there are some 130 different types of cruise missiles in the world, and approximately 75 countries have short-range anti-ship cruise missiles (ASCM). The accuracy of the cruise missile has increased with the use of GPS, active radar, television, infra-red, terrain mapping, and so on.

Cruise missiles have many advantages. They are short; therefore, they can be easily hidden, require little maintenance, and are capable of delivering weapons of mass destruction, and compare favorably with ballistic missiles. Cruise missiles can inflict large causalities, cause billions of dollars worth of damage and have considerable psychological impact. Further, it is very difficult to track cruise missiles because, they can maintain flight at a low level to evade radar, and have low visual, infrared and radar signatures, which makes it difficult for air defense radars to detect, track, identify or engage them. All qualities make cruise missiles a good option for states and terrorist organizations, which lack the technological and financial capability to build ballistic missiles.

There are many ways to acquire cruise missile. They can be purchased from countries by legal or illegal means. The states which are offering LACM for export are China, Russia, France, UK, South Africa and Pakistan. Russia is well-known for exporting LACMs. In June 2005, DPRK received cruise missile technology from Russia via Iran. China has sold anti-cruise missiles to Iran. Meanwhile, South Africa has offered the TARGOs air-launched LACM for export; Italy and Greece have purchased the SACLP EG from France; and Britain and France have sold the French Apache LACM (Black Shaeen) to the United Arab Emirates.

Second, cruise missiles can also be developed indigenously. China is developing two types of LACMs to be positioned against Taiwan. The latter is developing its Hsiung Feng-II ASCM, having a range of 1,000 to 1,500kms. Similarly, India is developing the Brahmos, with Russian assistance.

Third, existing missiles can be converted into cruise missiles. Short-range ASCMs can be converted into LACMs. But this is difficult and only a small number of the Chinese Silkworm and its derivates have been transformed into LACMs with ranges over 300km. Conversion of unmanned aerial vehicles (UAVs) into LACMs is also possible. UAVs are unarmed and reusable systems while cruise missiles are armed and not reusable. The modification of UAVs into LACM requires emplacement of explosives and competent remote operator to guide the UAV into its intended targets. Israel, for example, has announced that it is converting its Delilah UAV into cruise missiles.

Kit airplanes too, can be converted into weapons carrying full, autonomous cruise missiles. In general, kit airplanes have a cruising speed of 75 knots, range of 500km, weight of about 400kg, fuel and payload capacity of 200kg, and a short take off distance of 75 meters. A beginner's time to build a kit airplane is around 260 hours. The conversion of kit airplanes requires integrating and properly installing flight component systems but is cheaper, and requires less effort and skill. Recent years, have seen many companies willing to sell these flight component systems. Nearly 500 such designs are available with a range of 1,000km and a payload of 200kg.

The development and proliferation of cruise missiles is increasing. As cruise missiles are small, it is difficult to detect their proliferation, and they could be easily acquired by terrorist or other non-state actors. This situation is alarming as these missiles could penetrate even the missile defence of the US. While states will think twice before launching an attack on the US owing to its deterrent capabilities, terrorists, on the other hand, do not fear the US deterrent. The latter could use cruise missiles since they have not territory against which the US could retaliate. Similarly, while rogue states are far from developing ballistic missiles due to the technological and financial difficulties involved, they could develop cruise missiles in future. However, the US continues to pay greater attention to the ballistic missile threat and is busy in establishing missile defenses, which cannot assuredly intercept cruise missiles.