The deliberate creation of a separate section to authorize a separate federal entity is not a drafting error. The repeated and deliberate reference to one section but not another is not a drafting error. The refusal to grant equal authority to two programs authorized by two separate sections is not a drafting error. The decision to specifically reference section X but not section Y in a portion of a law that grants spending or tax authority is not a drafting error.
The clear text of the law repeatedly demonstrates that plans purchased via federal exchanges were never meant to be treated the same as plans purchased by state-based exchanges. Despite its assertions, the IRS was never granted the statutory authority to hand out tax credits related to plans purchased via a federal health exchange.
Source: thefederalist.com
