Question: I suspect being economically strong and independent aren't enough to become a super power in today world, I realised that US is slowly losing it's grip as a super power after it starts shifting focus on other research areas and staying away from making nukes. Given today technology, can a nation become a super power without having any nuclear programme? Sorry for my childish thinking but I think people would definitely listen when you can talk at over 250dB.

Answer: 
That is unknown ...
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Nuclear weapons have not been used in combat for almost 75 years. Their existence has loomed over geostrategic thinking, but nuclear strategy are all **untested assumptions.**

Once upon a time, [theorists](https://en.wikipedia.org/wiki/Herman_Kahn) wrote papers where widespread *evacuation* programs were seen as more significant than localized nuclear use. Others [seem](https://en.wikipedia.org/wiki/Force_de_dissuasion) to have thought roughly "any nuke is a nuke" and their very first strike would be a massive [countervalue](https://en.wikipedia.org/wiki/Countervalue) attack.

I consider it *quite* feasible that a major non-nuclear power could come close to superpower status using trade, cultural influence, and cyber power. Would they actually be a superpower? People would argue endlessly.

Consider virtual arsenals.
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Remember how upset the US are/were about Iraqi, Iranian or North Korean nuclear weapon programs? Well, South Korea, Japan and Germany presumably have no nuclear weapon programs, but their non-existing programs are much closer to the bomb than, say, Iran. And Japan probably could overtake North Korea in a few months, if they wanted to. They are *trusted* not to take that step.

* They have scientists who understand nuclear weapons engineering, if only so that their national security agencies can *evaluate reports* of other countries' programs. They would never rely on intelligence from the P5 alone.
* They have a civilian nuclear industry with plutonium stockpiles.
* They have at least tactical delivery systems.
**First to achieve Lunar/Space Colony.**

Say a multibillionaire sets his sights on space exploration. Before the slow engines of states achieve similar success, his country could be lauded SuperPower if they get first De FACTO ownership of celestial bodies.

The logistical capabilities that accomplishment grants, the information available to them. 

*And the sheer Bragging Rights.*

That makes you the sole state who controls a rare commodity, akin to China holding the Lion's share of rare earths.

Remember that Politics is the Art of looking the part.