You are wrong
Once the lease is signed, which presumably gives the lessee the mineral rights, the lessee can sell the minerals just about any where it wants. Legal possession of the minerals (or oil and gas in the case of drilling rights) goes to the lessee once the lease is signed. If you want to change that, it will require major changes in US law and reverse legal precedent since the day the US was founded.
However, there are some general restrictions having to do with countries such as North Korea, Iran, and even China when it comes to militarily sensitive products, but currently Canada (the intermediary) is not covered. Selling what could be construed as militarily sensitive materials to China this way is a very tricky issue, and it has been coming up a lot recently. But interpreting ownership of the ore in the way you want would just open up a can of worms far outside this issue and is not the way to deal with it.
