The design and manufacture of a bomber involves a complex set of technical challenges, including but not limited to the following:
Funding issues: The development and production of bombers requires huge financial investments. For example, the United States spent more than $20 billion on the development of the B-2** strategic bomber4. Such an investment is unaffordable for many countries.
Technical issues: Compared with fighters, bombers are more difficult to manufacture and require more advanced technology and a well-developed military aviation industry system. At present, there are no more than ten countries in the world that have the ability to independently develop fighter aircraft, and naturally even fewer countries that have the ability to develop bombers.4
The question of demand: The main role of strategic bombers is to carry tens of tons of ammunition for long-range raids and bombing, and the range is more than 10,000 kilometers. In general, few countries will have such a need. In addition, it is too difficult to manufacture, so many countries do not consider working on strategic bombers4.
In addition to the above-mentioned technical challenges, whether a country has bombers or not is also related to its technical capabilities. China, the United States, and Russia are all countries with strong aviation industry bases, and they all have deep accumulation and strong innovation capabilities in aero engine technology, composite material applications, communication and navigation technology, and other fields3.
Finally, political and economic factors are also important factors that affect whether a country has bombers or not. The possession of bombers was seen as a political means with a deterrent force that could not be underestimated. At the same time, the manufacture and maintenance of bombers also require stable economic support.
Summing up, from the point of view of aviation technology and capabilities, the reason why only China, the United States and Russia have bombers is their special advantages in terms of funds, technology, needs, and politics and economy.