... a considerable proportion of it, probably a very large
proportion, including most of the undesirable class, does not
come here of its own initiative but because of the activity
of the agents of the great transportation companies.... The
prime need is to keep out all immigrants who will not make
good American citizens.

In consonance with this spirit, the law of 1907 was passed. It
increased the head tax to four dollars and provided rigid scrutiny
over the transportation companies. The excluded classes of immigrants
were minutely defined, and the powers and duties of the Commissioner
General of Immigration were very considerably enlarged. The act also
created the Immigration Commission, consisting of three Senators,
three members of the House, and three persons appointed by the
President, for making "full inquiry, examination, and investigation
... into the subject of immigration." Endowed with plenary power, this
commission made a comprehensive investigation of the whole question.
The President was authorized to "send special commissioners to any
foreign country for the purpose of regulating by international
agreement ... the immigration of aliens to the United States."

Here at last is congressional recognition of the fact that immigration
is no longer merely a domestic question, but that it has, through
modern economic conditions, become one of serious international
import. No treaties have been perfected under this authority. The
question, however, received serious attention in 1909 when Lieutenant
Joseph Petrosino of the New York police was murdered in Sicily by
banditti, whither he had pursued a Black Hand criminal from the East
Side.