According to Cointelegraph, Ethereum Merge architect Justin Drake has expressed concerns about the relative security of Bitcoin compared to Ethereum. Drake, who played a pivotal role in Ethereum's transition to a proof-of-stake (PoS) system, suggested that launching a 51% attack on Bitcoin would be more cost-effective than on Ethereum. He estimated that such an attack on Bitcoin could cost around $10 billion. This perspective aligns with a previous statement by Grant Hummer, co-founder of Etherealize, who claimed that Bitcoin's security budget is insufficient. Hummer estimated that a successful 51% attack on Bitcoin could cost $8 billion, potentially decreasing to $2 billion in the future. A 51% attack occurs when an entity gains control over more than half of a blockchain network's mining or staking power, allowing them to manipulate the network.
Drake elaborated on the challenges of executing a 51% attack on Ethereum, noting that achieving 100% control would require more than half of the staked Ether. At the time of his comments, there were over 34 million staked Ether, valued at nearly $89.6 billion. This means that acquiring the necessary stake would cost approximately $44.8 billion. Given Ethereum's market cap of $316 billion and a 24-hour trading volume of $25 billion, the financial requirements for such an attack are substantial. Moreover, any attempt to accumulate this amount of Ether would likely drive up its price, further increasing the cost of the attack.
Matan Sitbon, CEO of Lightblocks, highlighted Ethereum's additional security measures, emphasizing the role of the community's social and economic coordination mechanisms. Drake also pointed out that Ethereum's PoS system allows the community to identify and penalize attackers through social consensus, a feature not available in Bitcoin's proof-of-work (PoW) system. This social layer, comprising the network's human participants, can decide on software changes to counteract attacks. Pavel Yashin from P2P.org mentioned that if centralization is detected, the community could implement a new fork, rendering the compromised chain obsolete. Hassan Khan, CEO of Ordeez, added that while a 51% attack is theoretically possible, practical barriers make it highly improbable for both Bitcoin and Ethereum. He noted that Bitcoin's PoW system requires significant computing power and energy, while Ethereum's PoS introduces economic and governance challenges that deter such attacks.
