Security, defence & exercises

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Prelims 2022 · Q34

Medium

Which one of the following statements best reflects the idea behind the "Fractional Orbital Bombardment System" often talked about in media?

Answer & explanation

Answer: (c) A missile is put into a stable orbit around the Earth and deorbits over a target on the Earth.

A Fractional Orbital Bombardment System (FOBS) sends a warhead into a low Earth orbit and brings it down over the target before it completes a full circuit — hence 'fractional'. Because it can approach from any direction, even over the South Pole, it is hard for early-warning radars to track. The Soviet Union built one in the 1960s, and it returned to the news in 2021 after reports of a Chinese test.

✓ (c) FOBS places a weapon in orbit around the Earth and then deorbits it onto a target, instead of following the arcing path of an intercontinental ballistic missile.
✗ (a) Deflecting or destroying an incoming asteroid is planetary defence (for example NASA's DART mission), not a bombardment system aimed at Earth.
✗ (b) Orbiting a planet several times before landing describes a planetary landing mission, unrelated to weapons.

Remember · FOBS: nuclear warhead put into low partial Earth orbit, deorbited onto target — evades radars facing the usual ICBM routes; Soviet system banned under SALT II (1979).

Sources

US Congressional Research Service, Defense Primer: Hypersonic Boost-Glide Weapons (updated May 2026) ↗ “a ballistic missile booster that carried the HGV into orbit before the HGV de-orbited and approached its target. Experts assert that this type of system might provide China with the ability to launch HGVs over the South Pole, thus evading U.S. early warning assets that track threats over the North Pole”
US Department of State: Treaty Between the USA and the USSR on the Limitation of Strategic Offensive Arms (SALT II), 1979 ↗ “After entry into force of the Treaty, fractional orbital missiles shall be removed and shall be destroyed pursuant to the provisions of subparagraph 1(c) of Article IX and of Article XI of the Treaty”

Question and answer: UPSC's official GS Paper I (2022, Series A) — paper ↗ · answer key ↗. Explanation: Minimalist IAS, checked 30 Sept 2026 (how we verify). Permalink ·

Prelims 2022 · Q86

Easy

Which one of the following statements best reflects the issue with Senkaku Islands, sometimes mentioned in the news?

Answer & explanation

Answer: (b) China and Japan engage in maritime disputes over these islands in East China Sea.

The Senkaku Islands are a group of small uninhabited islands in the East China Sea that Japan administers and China (and Taiwan) also claim, so China and Japan are in a maritime dispute over them. The other options describe things that have no basis: they are natural islands, not in the South China Sea, and no US base or ICJ ruling is involved.

✓ (b) Japan administers the islands, which it places under Ishigaki City, Okinawa. China and Taiwan press their own claims, which they began asserting around 1970-71 after a UN-linked survey pointed to possible oil under the seabed.
✗ (a) They are natural islands and rocks in the East China Sea, not artificial islands and not in the South China Sea.
✗ (c) The islands are uninhabited and no permanent American base has been set up on them to help Taiwan.
✗ (d) The International Court of Justice has not ruled on them, and the claimants are Japan, China and Taiwan, not South-East Asian countries.

Remember · Senkaku (Japanese name) or Diaoyu (Chinese name) islands: East China Sea, administered by Japan, claimed by China and Taiwan.

Sources

Ministry of Foreign Affairs of Japan, Senkaku Islands Q&A (archived copy) ↗ · reference work “it is only since the 1970s that the Government of China and the Taiwanese Authorities began making their own assertions about the Senkaku Islands”
Ministry of Foreign Affairs of Japan, About the Senkaku Islands (archived copy) ↗ · reference work “The Senkaku Islands are a group of islands located in Ishigaki City, Okinawa Prefecture”
US Congressional Research Service, The Senkakus (Diaoyu/Diaoyutai) Dispute: U.S. Treaty Obligations (R42761) ↗ “Japan, China, and Taiwan all claim sovereignty over the islands, known as the Senkaku-shoto in Japan, the Diaoyu Dao in China, and the Diaoyutai Lieyu in Taiwan. … Japan administers the eight small, uninhabited features, the largest of which is roughly 1.5 square miles.”

Question and answer: UPSC's official GS Paper I (2022, Series A) — paper ↗ · answer key ↗. Explanation: Minimalist IAS, checked 1 Oct 2026 (how we verify). Permalink ·

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