strata.[5] The
manufacturing-employers advocate "protection" which enhances the price
of their products, while usually favoring "free trade" in immigration
to cheapen their costs. What more natural than that laborers should
favor a policy of protection to labor, to keep foreigners from coming
here to be their competitors.

Sec. 9. #Divergent views of effects on population.# The foregoing views
of the effects of immigration upon wages, both of those favoring and
those opposing it, are short-time views, relating to immediate rather
than ultimate effects. If the immediate causes are continuously
repeated throughout the lives of successive generations the results
are for those mortal men as ultimate as anything that concerns them.
In this case it would make no difference to the millions of workers,
whose wages are depressed, if it could be shown that wages fifty or
a hundred years from now would be no lower as a result of continued
immigration than they otherwise would be; or to the employer that
wages would then be no higher. But to the social philosopher and to
the statesman, interested in the abiding general welfare, the ultimate
economic effects are of the greatest importance.

The question is: What will be the far-reaching, long-time effects of
immigration upon the general economic situation, as that determines
the welfare of the mass of the people? We confine ourselves here to
the economic effects, leaving aside as far as possible the racial,
moral, religious, political, and general social aspects of the
subject.

We are met at the outset by two divergent opinions as to the permanent
results of immigration upon the growth of population. The one is that
all immigrants coming to our shores are net additions, hastening by
so much the growth in density of population; the other opinion, the
displacement theory, is that immigration has the effect of checking
the natural increase of the native stock so much that it does not
materially change the total population, or actually causes it to be
less than it would have been had no immigration occurred.

Sec. 10. #The displacement theory; its fundamental assumption.# The
latter opinion which still has many upholders[6] was first advanced by
a distinguished economist, Francis A. Walker, but his first statement
of it referred only to the period between 1830 and 1860. The main
argument in support of this opinion was that in the three decades from
1830 to 1860 during which a lar