Mars and Minerva sit under the rose, considering the rusting implements of war. British peace has followed the war of independence in the States and the defeat of Napoleon in France. "Come stir up the wars, and our trade will be flourishing"
Zimmermann p. 33 is a fragment; broadside Bodleian 2806 c.17(449) is the basis for the description. Zimmermann's reference underscores the reliance of commerce on war; after all, the broadside notes, "Napoleon did make the money fly about" [a line shared with "The Grand Conversation on Napoleon"]. The rose may be a symbol for England (cf. "The Bonny Bunch of Roses" [Laws J5]) - BS
The effect of Napoleon on commerce is, at best, a debatable point. War production certainly helped some economies at some time (look what it did for the United States in World War II!).
But the Napoleonic Wars seem to have caused not growth but recession, or at least loss of personal wealth due to inflation, in Britain (see the versions of "Ye Parliaments of England" which blame economic woes on Napoleon). Napoleon's "continental system" was an embargo on British trade which might have proved fatal had it not been so widely flouted; the British government's massive spending on its military sucked capital out of the economy and damaged internal trade. Plus the army and navy required so many men that farming and industrial production suffered; it was the desperate British need to round up sailors for the navy that caused the impressment crisis and led to the War of 1812 with the United States.
Napoleon helped make the munitions makers rich (and that may be the reference here); historian Arthur Herman, whose outlook never manages to make it much beyond the deck of a navy ship, claims that in the period of the Continental System, "Britain's economy was booming. The wheels of the Industrial Revolution were humming... War had given Britain the biggest economy... in the world" (_To Rule the Waves_, p. 413; compare p. 406). Possibly, if you just count total output. But ordinary people suffered.
For more background on the Continental System and its economic effects, see the notes to "The Ports Are Open." - RBW