Quantum computing threat to Bitcoin is shifting from theory to reality. For years, the industry has debated whether quantum machines pose a genuine risk—now we're seeing actual proof. Here's the core issue: if quantum computers become powerful enough, they could potentially break Bitcoin's ECDSA signature algorithm. That's the cryptographic foundation protecting $BTC transactions. If that fails, a massive number of bitcoins stored in vulnerable addresses could be exposed. It's not happening tomorrow, but the timeline is shortening. This is why researchers and developers are already exploring post-quantum cryptographic solutions for blockchain infrastructure.