What allowed the united states to claim american samoa apex?

Tripartite Convention--this convention settled the dispute between the US and Germany over claims on Samoa. 

The US and Germany had been in Samoa due to the islands being opened to missionary work and then later trade. When Germany came onto the island, the US was prepared to fight for their right to be there. The Tripartite Convention settled the dispute with the two countries agreeing to split the islands. 

Upheld the 1st amendment according to the u.s constitution. freedom of speech being limited in this case yes national emergencies