Foreign capital, when it is invested in productive enterprise is good. It reduces the cost of borrowing money, which stimulates your economy, promotes value creation, etc. Assuming you believe that this sort of economic activity is a net good, that is. (And I think that even a dyed-in-the-wool socialist will agree, under the right tax system.)

Foreign capital, when invested into a limited, rationed, speculative resource, that is also required for life - like say, housing, is a ----ing nightmare.