The Anglo-Spanish war stretched across both sides of the Atlantic. While the Western Design focused on the Caribbean, the war extended into the Mediterranean as well. Cromwell formally declared war against Spain in the autumn of 1655, and Philip IV of Spain followed suit in March 1656. Between the conquest of Jamaica and Cromwell's death in September 1658, however, the war effort carried little momentum. Two major English triumphs marked the period: in September 1656 Captain Richard Stayner seized Spanish treasure ships, and in April 1657 Admiral Robert Blake sank the Spanish plate fleet. These important victories helped justify the pursuit of an expensive transatlantic war; the cost of maintaining the fleets placed a severe strain on the treasury, and in between the dismissal of the first Protectorate Parliament in January 1655 and the calling of the second in September 1656 supply was scarce. Yet in the months between naval successes the pace of war was sluggish and the English fleet found few targets to engage. Philip IV, still bound in war against France, was not eager to engage in a naval battle with England, preferring instead to commission Dunkirk and Ostend pirates to attack English vessels. Spanish merchants, reluctant to risk the capture of their ships and goods, used Dutch middlemen as carriers. As the English agent in Portugal Philip Meadowe summarized the situation, the Protector was at war with an enemy that ‘will neither fight nor trade’.

Apologists for the war consequently had a challenging task. As discussed in the previous chapter, after the stricter censorship regulations imposed in the fall of 1655 Nedham's Politicus and Publick Intelligencer largely comprised the newsbook market. While Nedham did what he could to mobilize support for the war, often for weeks and months at a stretch there was little substantive news to report. To supplement news coverage, promotion of the Spanish war and imperial expansion issued from a variety of media. These apologies have, on the whole, received little attention. Scholarship treating the Anglo-Spanish war tends to concentrate rather narrowly upon the Western Design and the problems it posed for the Protectorate: the defeat at Hispaniola, the struggles to settle Jamaica, the disappointment of government officials and the unpopularity of the war.