Big time

Clarification: this question is about them acquiring nuclear weapons in addition to the ones they already have, yes?

As dawn broke over the Central Pacific in 2030, the world awoke to a new nuclear power. The Republic of Nauru, once primarily known for its phosphate mining, had clandestinely developed a nuclear arsenal, marking a dramatic pivot in its national defense strategy and international standing.

The seeds for Nauru's nuclear ambitions were sown in the late 2020s. Facing existential threats from rising sea levels and seeking a deterrent against external economic pressures, Nauru embarked on a path less traveled. With a population just shy of 11,000, the endeavor seemed quixotic, yet the strategic calculus was driven by a blend of desperation and visionary leadership.

The initiation of Nauru's nuclear program was shrouded in secrecy. Utilizing the vast revenues accumulated from decades of phosphate exports, Nauru discreetly assembled a team of international scientists and engineers under the guise of developing renewable energy projects. By 2028, the small island had constructed a sophisticated underground facility capable of enriching uranium.

The revelation of Nauru's nuclear capabilities sent shockwaves through the international community. Initial skepticism quickly gave way to alarm as satellite imagery confirmed the existence of a missile launch site. The United Nations Security Council convened an emergency session, but Nauru's diplomatic maneuvering, leveraging its newfound status, stymied punitive measures.

On October 14, 2030, Nauru conducted its first nuclear test, codenamed "Oceanic Light." The detonation, carried out on an uninhabited islet within its territorial waters, demonstrated a yield of 10 kilotons. This audacious display of nuclear prowess was broadcasted live, showcasing a defiant Nauru asserting its place on the world stage.

The Nauruan nuclear weapons program fundamentally altered the strategic landscape of the Pacific. Small island nations, previously seen as peripheral actors, were now viewed through the lens of potential nuclear proliferation. Major powers, particularly those with vested interests in the Pacific, reevaluated their foreign policies, emphasizing diplomatic engagement over coercion.