My problem with this answer is two fold:
1. I think if we look at capital as a whole and worry less about such
ratios as unproductive to productive labor within national boundaries or
only the labor directly employed by US companies abroad, we will find that
in the "foreign" units to which multinationals outsource or from whom
commercial enterprises buy do employ more productive labor in relation to
unproductive labor.
2. When more US labor was used in the production of consumer or mass
produced goods, it seems to me that that wage norms regulated the distance
between, say, an auto worker and an aircraft machinist. There seems to be
no such regulation for the wages of commercial workers. In this case, I
think their wages are so low that if even if their gross employment is
growing and thus the ratio of unproductive to productive labor, they can't
possibly be responsible for much deduction from surplus value.
Best,
Rakesh