In the long term you are right. But in the short term, probably not. This isn't the time to invest in copper. China is doing everything they can to cool down their property market => less demand for copper.
Copper jumped recently because China's largest melter(Jiangxi Copper) reduced production due to environmental reasons.
So it's not a desperate demand pull from rapidly growing economies that is charging prices higher, its a collapse in supply.
And there are also inflation concerns in the U.S. ... If US inflation turns further south, copper will likely follow.
on a macro scale its always hard to call global demand of a commodity. many different factor at play all at once i have not invested in the sector yet myself thanks for commenting