Final answer:
North Korea attempted to develop nuclear weapons in the early 2000s, leading to its first nuclear test in October 2006, which raised international security concerns.
Step-by-step explanation:
Country Developing Nuclear Weapons in the Early 2000s
The country that attempted to develop nuclear weapons during the early 2000s was North Korea. This was a significant concern for the international community due to the potential implications for regional and global security. The development of nuclear weapons by North Korea was part of a long-term project aimed at ensuring the country's security in the face of international pressures. The official confirmation of North Korea's nuclear capabilities came with its first nuclear test in October 2006, a move that heightened tensions and prompted international efforts to deter further nuclear proliferation in the region.