51 Percent Attack is an attack on blockchain that dominates 51 percent of its overall computation rate (hash rate). Assuming the current Bitcoin blockchain hash rate is 126.13 Exahash per day, then 51 Percent Attack should be able to dominate up to 64.3263 Exahash per day.

In this case, the Bitcoin miners have the potential to carry out the attack, because they are the ones who have the greatest resources. The fact is that currently, the Bitcoin mining hash rate globally is controlled by miners from China which reaches 2/3 or around 66.66 percent. This means Bitcoin miners from China, if they want, they can do a 51 Percent Attack on the Bitcoin blockchain.

If you ask why they don't want to attack, the answer is simple, because it will mess with the Bitcoin ecosystem itself, including the crypto asset ecosystem in general. There will be distrust of Bitcoin, which in turn reduces the value and degree of Bitcoin itself. However, the chances of success at 51 Percent Attack are also uncertain. This means that considering the enormous cost per day, then the likelihood of confusion and uncertainty, hackers have to think a thousand times.