The benefits to mining the Kuiper Belt outweigh the risk, although they are currently hypothetical and would require significant advances in technology and infrastructure to be realized. Here are a few reasons why we need to mine the Kuiper Belt:

• Access to rare resources: The Kuiper Belt is thought to contain a variety of resources that are rare on Earth, including water, nitrogen, methane, and other elements. These resources could potentially be used to support human settlement and industry in space, or even to supplement Earth's dwindling resources.

• Scientific exploration: The Kuiper Belt contains many unique and scientifically valuable objects, including comets and dwarf planets. Mining the Kuiper Belt could potentially provide us with new insights and knowledge about the formation and evolution of our solar system.

• Economic opportunities: If we can develop the technology and infrastructure to mine the Kuiper Belt, it could potentially open up new economic opportunities for space-based industries and resource extraction.

• According to some estimates, a single asteroid with a diameter of one kilometer and a platinum concentration of 10 parts per billion could have a value of up to $5.4 trillion. 

However, it is worth noting that these potential benefits are currently speculative and would require significant investment and innovation to be realized. Additionally, there are also significant ethical and environmental concerns associated with mining the Kuiper Belt.