By its nature, USX is an overcollateralised stablecoin, backed by USDC/USDT (other assets may be additionally whitelisted at a later date) and therefore inheriting their security.
It is minted at will by whitelisted institutional market participants upon deposition of requisite collateral, which is provided of equivalent value (that is to say, overcollateralisation is not a result of demanding extra collateral of the minters). Redemption is available only to the same participants and has possession of a quantity of USX as its only prerequisite.