At least it was nationalised then, so there was some justification; but now it is privately owned. If BMW is serious, and decides to close the plant in the absence of a government subsidy, only then should New Labour take action. They could buy the (closed) plant cheaply, or nationalise it, then sell it in a privatisation or management buy-in/buy-out. That would give BMW competition instead of subsidy, and would genuinely help to protect British jobs, rather than German shareholders' interests.
BMW knew what they were buying at the time; nothing has changed. Mr Blair should call their bluff.
R D PHILLIPS