/u/MasterFubar is right though. Stripping private companies out of the supply chain is a horrible idea. Universally, state operated mines suffer substandard productivity, often have issues with supply of goods and materials as purchases get tied up in governmental controls and barriers and struggle to attract and hold foreign talent. That last point is so easily overlooked but can make the difference between a profitable operation and a failure.

You can decide to write off losses as the cost of maintaining control, but in practical terms you have just stripped significant revenue streams from your government through royalties and taxes.

Government permitting contracts may sometimes have clauses ensuring local supply regardless. You lose a lot and gain in practical terms nothing.