What are the US views on dual citizenship? Can a US citizen hold dual citizenship?

Almost anyone can hold dual citizenship, as long as guidelines are followed. For instance, my son was born in US to Canadian parents so that made him elligible for CDN and US citizenship and passports which he holds.

U.S. law does not say anything about dual citizenship. It doesn't acknowledge the existence of other countries' citizenships at all. If you are a U.S. citizen, then in its eyes you are only a U.S. citizen like all other U.S. citizens.

U.S. will never ask you to give up another country's citizenship, when you naturalize or any other time (that country could take it away from you under certain circumstances, e.g. naturalization, but the U.S. will never ask you to give it up; unless you want to work for some top secret government agency; some of those will ask you to renounce other citizenships in order to get a security clearance); and getting or having other countries' citizenships can never affect your U.S. citizenship, unless you intend to give up your U.S. citizenship.