How could nuclear energy which is classified as a nonrenewable energy resource be reclassified as an inexhaustible energy resource?

Nuclear energy is a non-renewable source since there is a very tiny amount of Uranium-235, whose fission results in nuclear energy. If a more abundant element could be used in nuclear reactors, such as, say, nitrogen or oxygen, it would effectively become inexhaustible. However, current technology does not allow for this since these atoms are too small to be accurately and repetitively bombarded (which is a key part of the fission process).