How suitable is the term "blacks" to specify an ethnic group?

Solution 1:

There are official US racial definitions that government agencies follow, in a accordance with a Office of Management and Budget (OMB) directive, as explained here. Two of the definitions are

Black or African American. A person having origins in any of the black racial groups of Africa. Terms such as "Haitian" or "Negro" can be used in addition to "Black or African American."

White. A person having origins in any of the original peoples of Europe, the Middle East, or North Africa

So keep in mind that some original people of Africa and their descendants, for example of Egypt, Libya, Tunisia, Algeria, etc., are considered "white", at least according to official US definitions.

The term "African-American" came into wide-spread usage after Jesse Jackson endorsed in 1988, as explained in the 31 January 1989 New York Times article 'African-American' Favored By Many of America's Blacks.

However, subsequently there has been some backlash against this term from blacks. See for example:

Why I'm Black, not African American Los Angles Times 08 September 2004.

I'm Not African American, I'm Black Ebony 2012

Even Jesse Jackson was recently (4 April 2017) quoted as saying the phrase "blacks building slave ships", as explained in Rev. Jesse Jackson: Latinos Building Border Wall is Like Blacks Building Slave Ships

The naming of black organizations such as Blacks in Government and National Association of Blacks In Criminal Justice further shows that "blacks" is not an offensive term.