Foremost, I think you need to challenge your conception that Boston, and the colony of Massachusetts Bay more broadly, was an "isolationist community." While certainly founded on Puritan ideals, Puritans were not people who necessarily shunned the pursuit of profit. The Puritans were a group of separatists who wished to radically purify the Anglican Church of the remaining Catholic aspects. While the Puritans were notorious for their chastisement of both the Church of England and the Catholic Church for its materialism, central to the establishment of the Massachusetts Bay Colony was a strong communal belief that the colony could only thrive if each member participated in building a colony that was "a beacon upon a hill." While this is popularly depicted as a statement about moral purpose, Puritans also understood that they needed to create a financially viable colony in order to continue in their religious pursuits. Therefore, the Puritans were not inherently isolationist; rather, colonists in Massachusetts Bay quickly looked to make their colony profitable. Although they were not opposed to profits, as Christine Heyrman notes in Commerce and Culture: the Maritime Communities of Colonial Massachusetts, 1690-1750, increasing materialism through the eighteenth century did create a conservative backlash among strict Puritans who argued increasing profits were leading Puritans away from their roots. This backlash, however, created a more unified New England rather than a divided one.

Fishing was one of Bostonians earliest economic ventures. During the seventeenth and eighteenth century, the market for fish was booming. In Catholic Europe, fish was consumed in lieu of meat on ordained days and throughout the Caribbean, fish was economical option for feeding large slave populations. Harold A. Innis' The Cod Fisheries: The History of an International Economy and W. Jeffrey Bolster's The Mortal Sea: Fishing the Atlantic in the Age of Sail document how English fishermen had been fishing of the Grand Banks of Newfoundland and costal L'Acadie (Nova Scotia) for nearly a century and New England fishermen joined in this pursuit and a few fishermen were able to build large fleets and turn handsome profits by the mid-eighteenth century. As colonists pushed west from the coast fishing exports to Europe were supplemented with grain from the interior and lumber from the interior. The woodlands of interior New England also gave rise to ship building industry in Boston.

With the growth of exports to Europe and the Caribbean came an influx of imports. Most important of these imports to colonial economy of New England was Caribbean sugar and molasses, from which distillers created rum. Although neighbouring Newport was most widely known for their rum (See Eliane Forman Crane's A Dependent People), plenty of Bostonians were also in business. Rum was lucrative for trade, especially along the "slave coast" of western Africa where, as Robin Law describes in Oudiah: The Social History of a West African Slaving Port, New England rum was often the standard currency for trade. The slave trade also benefitted New England ship builders who profited from both building and outfitting slave ships. In addition, merchants built profits from the slave trade as they invested in the transportation of human capital.

While the trade of goods certainly helped build Boston into a commercial port, these pale in comparison to the importance of the British navy. During the early colonial wars of the 18th Century, the British became more invested in New England as they waged war against the French in Quebec and L'Acadie. During the Seven Years War, the British sent supplies, vessels, and men flooding into Boston. While Bostonians had established themselves as merchants, the influx of capital brought with the British navy transformed Boston into a commercial port for North America.