Quantum computing speedup theory relies on exploiting symmetric structures in quantum systems to achieve exponential acceleration. Researchers have identified Hilbert-space symmetric structures in multiple-quantum operator algebra spaces as key resources for quantum computing speedup. By manipulating these structures, quantum computers can potentially solve complex problems more efficiently. The Subspace-selective unitary manipulation method is a new approach that leverages these symmetric structures to enhance quantum computing capabilities. This development has significant implications for the field of quantum computing, as it could lead to breakthroughs in simulation and computation1. The ability to harness these fundamental resources could revolutionize various fields, including cryptography, by rendering certain encryption methods obsolete. So what matters to practitioners is that advancements in quantum computing speedup theory, such as Subspace-selective unitary manipulation, are bringing us closer to a reality where quantum computers can outperform classical computers, thereby rewriting the rules of computation and cryptography.