What is missing is not technology but a reason to go.
"At 1997 prices, a relatively small metallic asteroid with a diameter of 1.6 km (0.99 mi) contains more than 20 trillion US dollars worth of industrial and precious metals." [1]
Spot-checking (pun not intended), those metals are currently up as much as an order of magnitude over their 1997 prices. So that same small-ish asteroid could be worth something more along the lines of a quarter petadollar.
If that's not sufficient reason to strip mine the asteroid belt, I don't know what is.
I bet the value of metals on Earth already far exceeds this many times over. And what do you think would happen to the price of metals if you had this huge supply?
"At 1997 prices, a relatively small metallic asteroid with a diameter of 1.6 km (0.99 mi) contains more than 20 trillion US dollars worth of industrial and precious metals." [1]
Spot-checking (pun not intended), those metals are currently up as much as an order of magnitude over their 1997 prices. So that same small-ish asteroid could be worth something more along the lines of a quarter petadollar.
If that's not sufficient reason to strip mine the asteroid belt, I don't know what is.
[1] https://en.wikipedia.org/wiki/Asteroid_mining