Global influence is won by a strong financial position. Weapons are merely a cart, pulled by horses that include tax base, borrowing capacity and GDP. These are the things that buy influence, whether through guns, elections or direct investment. (Conversely, empires collapse for lack of money.)
Nations seeking influence focus all their energy on raising their own people’s aggregate income, which increases private-sector financial strength, as well as the tax base.
This means investing mainly in education, infrastructure, public safety and rule of law, while avoiding resource drains like civil strife and, especially, external wars.
Countries that did this single-mindedly in recent decades — China, South Korea, Japan, Singapore — gained significant influence in a short time. Countries distracted by internal strife — Thailand, Malaysia — gained less. Countries that didn’t prioritize at all — the United States — lost relative influence.
Any country that is not primarily focused on increasing sustainable national income is off its game. It will lose relative influence over time. If your country under-educates its people, encourages consumer debt, and prioritizes spending over investment, it will decline. It really is that simple. We just get lost in the details.