U.S. Baptists have exported their disunity and have thereby negatively affected the effective Christian witness of Baptists in a number of countries, Callam observes.
In 1911, the Northern Baptist Convention and the Free Will Baptist General Conference forged a church union. This was perhaps the first example of organic church unity in the 20th century.
Since that time, the resulting group has led the way, among Baptists in the United States, in developing and manifesting a positive ecumenical commitment and outlook.
In 1950, Northern Baptist Convention changed its name to American Baptist Convention and invited other Baptist groups in the U.S. to unite under the new umbrella.
Again, in 1972, the organization changed its name to American Baptist Churches, USA, and renewed their invitation, which received neither a warm welcome nor a positive endorsement from other Baptist groups.
American Baptists have pursued organic union with other church groups, such as the Disciples of Christ and the Church of the Brethren.
With the latter, with whom bilateral dialogue took place between 1973 and 1976, the interaction ended with the two partners signing an agreement on mutual recognition.
Like American Baptist Churches USA, African-American Baptists in the U.S. once expressed a longing for greater Baptist denominational unity in the country.
In 1895, three African-American church organizations - the Consolidated American Baptist Convention, the Baptist Foreign Mission Convention and the National Baptist Educational Convention, formed respectively in 1866, 1880 and 1893 - united to form the National Baptist Convention of the United States of America.
They elected a former enslaved person and an outstanding orator, Elias Camp Morris, to be their first president.
In the fourth year of his presidency, Morris thundered, in his presidential address, "From Maine to California, we are one, notwithstanding the efforts of designing men to disrupt the Convention by making false publications concerning it."
Morris identified as "one of the prime objects of the promoters of this Convention to obliterate all sectional lines among Baptists and have one grand national society, which would know no North, no South, no East, no West; and in this we have been successful." Morris could never have predicted what would become of black Baptist unity in the U.S.
Although the process of aggregating the statistics provided by the different U.S. Baptist groups is fraught with enormous challenges, a fair conclusion is that today, the U.S. remains the country with the largest Baptist population. It makes the Baptist World Alliance the only Christian World Communion with the majority of its adherents residing in the United States.
Within the BWA, 20 Baptist groups in the U.S. are currently listed with reported membership of more than 19 million. Besides these groups, numerous Baptist organizations have emerged over the years.
This development once prompted distinguished British Baptist historian, Ernest Payne, to complain about the "bewildering disarray" of the "flourishing Baptist of the United States."
In a not sufficiently known publication, "The Twelve Baptist Tribes: A Historical and Statistical Analysis," a noted Baptist church historian, Albert Wardin Jr., compiled a list of Baptist groups in the U.S.
He categorized them into 12 tribes and estimated their numbers (in 2007) as 28 million. The detailed list includes groups with rather memorable names, such as Two-Seed-in-the-Spirit Predestinarian Baptists.
U.S. Baptists have made an outstanding contribution to international mission. In many countries, their witness continues to attract widespread respect and appreciation.
Yet, this distinguished contribution has been marred somewhat by the fact that it has been compromised by disunity.
In other words, U.S. Baptists have exported their disunity and have thereby negatively affected the effective Christian witness of Baptists in a number of countries.
The problem of Baptist disunity in the global south is exacerbated when one combines the U.S. example with the separate witness of overseas missionary organizations in the United Kingdom, mainland Europe and Australia, for example.
Concern for church unity led the North American Baptist Fellowship (NABF), a BWA regional fellowship, to engage in theological dialogue with the Lutheran Council in the USA (LC-USA) from 1979 to 1981.
In this period, the Lutheran Church in America, the American Lutheran Church, the Lutheran Church-Missouri Synod and the Association of Evangelical Lutheran Churches were members of the LC-USA.
The published report of the three-year dialogue had a salutary effect on the international dialogue involving BWA and the Lutheran World Federation.
I dream of the renewal of NABF's interest in church unity in general, and Baptist unity in particular. What a positive effect this could have on Baptist witness both in the United States and around the world!
Neville George Callam, a Jamaican, has been serving as general secretary and chief executive officer of the Baptist World Alliance since his election in Accra, Ghana, in 2007. He is retiring at the end of 2017. A version of this article first appeared on his BWA blog. You can follow BWA on Twitter @TheBWA.