Evenly placed three quarters of the sprint, Bolt forged ahead in that final part of the track to deliver his second Olympic 100 metre Gold having won in Beijing.
Compatriot Yohan Blake finished second in 9.75 and USA's Justin Gatlin 9.79 in third just pipping his fellow countryman Tyson Gay 9.80.
Seven of the 9 in the final ran under 10 seconds, which was really under eight as Asafa Powell stopped with a calf injury seventy metres in.
Moreover, Usain Bolt ran through to the tape without slowing at the end and didn't even look around as has been his usual practise which illustrated the pressure on him to perform after so much hype about his physical conditioning.
Blake's second place, who beat Bolt in the Jamaican Olympic trials was the favourite under such circumstances but in then end, having witnessed the semi-finals, it was going to be Bolt's day.
Moreover, Bolt has become only the second man in Olympic history to win the 100 metres two Olympics in a row after Carl Lewis in 1984 Los Angeles and 1988 Seoul (after Ben Johnson was disqualified as a drugs cheat). .
It was the first time for many Olympic 100 metre finals that all three Americans reached the final.
The semi-final results were revealing with the first won by USA's Justin Gatlin 9.82 with the Netherlands Churandy Martina second and Jamaican's Asafa Powell third.
The second semi final saw Usain Bolt 9.87 (Jamaica) followed by Ryan Bailey (USA) and Richard Thomson of Trinidad.
The third semi-final Jamaican's Yohan Blake 9.85 followed by USA's Tyson Gay and Britain's Adam Gemili in third whose time of 10.06 meant he missed out on the final with the slowest of the 3rd placed times.
Interestingly, had the Olympic 100 metres functioned under British Industrial Law (Olympic athletes are not unlike cricketers in that it's their business within trade laws) - Bolt would have been disqualified for wearing a religious symbol necklace. Recently a Christian woman lost her appeal after being sacked from British airways for wearing such a symbol.