A real economy does not have a set of fixed tasks to be carried out. Jobs exist,are created, and destroyed as a function of supply and demand. Nasty jobs, if the supply of labour is limited, will either pay more to attract recruits or be eliminated by automation or some other form of substitution, or more likely, some combination of these.

The folly of attempting to use immigration to solve labour 'shortages' can be seen all over Europe. In Britain, instead of letting the textile industry in north-west England go out of existence in the 1950s and 1960s we imported labour to work in the dark, satanic mills. The textile industry disintegrated anyway, but the people and their descendants remain as a poor and embittered underclass.

Business, especially big business, will always try to con governments and other 'leaders' into providing cheap labour. The response of government should always be to tell business to get stuffed. If the price of labour is too high for your business to function, you need to innovate,relocate, or get in to some other type of business. This is called 'the market'.

Those who think that we need to import lots of unskilled labour should bear in mind that some forecasts predict that 15 million jobs will be eliminated by automation over the next 20 years. For this reason alone, we really do not want to import anything other than small numbers of highly skilled people.