Absolutely, so the blockade is a knife that cuts both ways, and effectively ruins the ability of the US to pay premiums on municipal and transportation bonds owned by British subjects. As I have written before, the economies and the populations were intertwined after 1844-46, and Britain would be engaged in a economic war with a part of its own population if it blockaded the US. The British liberals might suffer the most in that economic war, but they were unlikely to suffer quietly.
According to the British statistics, the United States represented £19m of £121m exports (15.9%) and £28m of £160m imports (17.3%) for 1862.* In 1863, the relative importance of the US dwindled: £20m of £142m exports (13.9%) and £20m of £164m imports (11.9%). What this shows is that access to the British market is far more important to the United States, in terms both of exports and imports.
* Note that these figures are not strictly directly comparable, as US government years end on 30 June and UK government years end on 31 March.