The Irish Famine was a useful pretext for Peel to repeal the Corn Laws and historians have debated the real reason why he decided to repeal them. One possible reason was that the Anti-Corn Law League was pursuing a successful campaign of voter registration to enfranchise free trade votes and Peel had his eye on the next election, so this might have scared him into pushing for repeal before the election due in 1848.

Another possible reason was fear of revolution. This was the time of the 'Hungry Forties' and the rise of Chartism. Peel and his generation grew up in the shadow of the French Revolution and fighting the next election on denying cheap food for the poor Peel considered dangerous. The Duke of Wellington said that "good Government for the country is more important than Corn Laws or any other consideration". Britain was the first country to industrialise, with the correspondent growth of cities filled with manufacturing workers who needed abundant cheap food that could only be supplied by untaxed imports. A poor, hungry proletariat they viewed as a ripe bed for the seeds of revolution to grow.

Intellectual opinion by the mid-nineteenth century had moved in favour of free trade. Not only Adam Smith's Wealth of Nations (1776) but also Ricardo's On the Principles of Political Economy and Taxation (1817) and other political economists were arguing in favour of free trade. There was no comparable British political economist publishing protectionist works at this time. Intellectual opinion filtered through to the political class and influenced them. For example, Peel said "I have read all that has been written by the gravest authorities on political economy on the subject of rent, wages, taxes, tithes". William Gladstone, who as Chancellor of the Exchequer in the 1850s and 60s completed the work begun by Peel in lowering or abolishing tariffs, was Peel's political pupil and was converted to free trade during his time at the Board of Trade in Peel's government.

The economic arguments for free trade advocated by political economists came to be seen as 'scientific', with protectionism viewed as unenlightened, irrational or motivated by class interests of the landowners at the expense of everyone else. It is no coincidence that radicalism (which emerged in the 1820s) fused Ricardian economics with universal suffrage. Radicals claimed that Parliament would never legislate for free trade whilst the suffrage was limited to the wealthy elite. Enfranchise those who would benefit from free trade, the poor, and free trade legislation would follow. The Radicals went on to form the Liberal Party with the Whigs, and one of the Liberal Party's fundamental, core principles was Free Trade.

Another reason apart from the economic arguments was also the political arguments for free trade. Cobden and Bright argued that if Britain converted to free trade, the rest of Europe would follow and then everyone would trade freely with each other and the world would enter an era of universal peace and disarmament. The interests opposing this development (so this theory went) were the reactionary landowning aristocrats who also happened to be officers in the Army. As Cobden explained:

Free Trade! What is it? Why, breaking down the barriers that separate nations; those barriers, behind which nestle the feelings of pride, revenge, hatred, and jealousy, which every now and then burst their bounds, and deluge whole countries with blood; those feelings which nourish the poison of war and conquest, which assert that without conquest we can have no trade, which foster that lust for conquest and dominion which sends forth your warrior chiefs to scatter devastation through other lands, and then calls them back that they may be enthroned securely in your passions, but only to harass and oppress you at home.

Free trade would not only give you international peace, Cobden is saying, but it would destroy the power of the aristocratic landowners who dominate Parliament and oppress the working class such as the 1819 Peterloo massacre. (Conversely, the leading protectionists Disraeli and Bentinck defended Protection on the grounds that it preserved Britain's territorial constitution based on a landowning aristocracy.)