Contractors, Article 4. Classifications. 7058. (a) A specialty contractor is a contractor whose operations as such are the performance of construction work requiring special skill and whose principal contracting business involves the use of specialized building trades or crafts.
The United States declared war on Germany for many reasons. One of them was the sinking on neutral ships and the lusitania which killed about 148 Americans. This was not the immediate cause, another is propaganda which persuaded public opinion.
By adhering to the pledges, Germany averted war with the United States in 1915 and 1916. In January 1917, however, Germany decided to resume unconditional submarine warfare, fully aware that renewed surprise attacks on merchant and passenger ships would likely prompt the United States to declare war.