[1] His father, Mathew Carey (1760–1839), was a native of Ireland and an influential economist, political reformer, editor, and publisher whose patrons included Benjamin Franklin and the Marquis de Lafayette.

[7] The same year that Essay on the Rate of Wages was published, Carey retired from active business with a fortune and devoted his time to economics and related work.

[10] Carey continued to ground his thinking in standard laissez faire doctrine, writing that "Governments have arrogated to themselves the task of regulating the currency, and the natural effect is that nothing is less regular."

"[11] Subsequent scholars have challenged Carey's claim of a sudden change of heart by pointing to his earlier opposition to the English occupations of Ireland and India and his support for Friedrich List and the German Zollverein.

[11][12] In 1845, in a pamphlet entitled Commercial Associations in France and England, Carey began to reject wholesale the "British" economics of Thomas Malthus and David Ricardo altogether and sought to develop a critique of their underlying assumptions.

Over the course of ninety days in 1848, Carey expanded on this view by writing Past, Present, and Future,[12] which he said was "designed to demonstrate the existence of a simple and beautiful law of nature, governing man in all his efforts for the maintenance and improvement of his condition... which, nevertheless, has hitherto remained unnoticed."

The work argued in favor of a marriage of industry with capital and the necessity of maintaining domestic markets to promote prosperity; it was met with derision from Manchester school economists.

[11] The same year, while living in Burlington, New Jersey,[11] Carey founded The Plough, the Loom, and the Anvil, a periodical journal of economic development, with John Stuart Skinner serving as its publisher.

This stance was adopted by much of the Northern press and has been partially credited for influencing Russia's reciprocal support of the Union during the American Civil War and the opposition of Great Britain and France.

[19] After leaving the Tribune, Carey took two tours of Europe, where he personally met with John Stuart Mill, Count Cavour, Alexander Humboldt, Justus von Liebig, Michel Chevalier, and other leading men.

He received three votes for Vice President at the 1856 Republican National Convention and served as a fundraiser, soliciting Philadelphia manufacturers for donations without assigning his beliefs to the party as a whole.

[21] Immediately after the election, which ended in defeat, Charles A. Dana asked Carey for his support in broadening the party's base, "a principle alone not being sufficient.

"[23] The ensuing House debate mostly dealt with slavery; one of the few Representatives to focus on protection was Justin Smith Morrill of Vermont,[22] who would become the leading proponent of Carey's theories during the American Civil War.

In a public debate of letters with William Cullen Bryant on the causes of the Panic, its relationship to slavery, and the Republican response, Carey argued that, "In [Pennsylvania and New] Jersey, the tariff is the one and almost the only question.

In most Western states, the party was divided, and Senator Henry Wilson, who previously pledged New England's support, urged Carey to be cautious.

[27] Republicans in the United States House, led by Justin S. Morrill and James H. Campbell, passed a protective tariff at Carey's urging, though it languished in the Senate into winter.

The platform ultimately declared, "while providing revenue for the support of the general government by duties upon imports, sound policy requires such an adjustment as to encourage the development of the industrial interests of the whole country."

[33] By July, Morrill reported to Carey that although "[Chase's] Philosophy is Free trade or ad valorems," he was "willing to yield" on tariff policy amid the growing cost of the American Civil War.

"[34] Carey also used his influence to secure key appointments in the Treasury Department for protectionists, including his trusted adviser Dr. William Elder as the lead tariff architect in the administration.

[33] In the winter of 1860–61 amid Southern secession, Morrill and Campbell pressed tariff protection in the lame duck Congress, and Carey personally went to Washington to direct lobbying efforts.

[20] In March 1865, Carey published a series of letters written to the Speaker of the House Schuyler Colfax during the Civil War, entitled "The Way to Outdo England Without Fighting Her".

In a series of public letters, he accused Wall Street banks of artificially inflating the cost of capital and predicted that a swift contraction would lead to chaos, economic paralysis, and political rebellion, particularly among farmers in the West whose mortgage rates would increase.

[21] Carey argued that ultimately, a causal chain could be drawn through "separation of [men], centralization of the mass, subjection of the many to the powerful few, slavery, stagnation, [and] decrease of real civilization.

"[38] Carey's rejection of orthodox English economic theory was borne of a belief that the state, as the coordinating power in society, must intervene to prevent private advantage from working public mischief.

Carey argued for developmentalism, positing that state intervention was necessary to remove "the obstacles to the progress of younger communities created by the action of older and wealthier nations.

[38] Carey argued this theory was the basis for the British policy of imperialism and free trade, by which the Empire intended to establish a global monopoly on both manufacturing and shipping centered on London, while other nations were resigned to exporting raw materials.

[38] Carey emphasized that the final result of industrialization would be the establishment of "perfect free trade" between developed nations, whose range of production would be limited only by absolute natural barriers.

[20] He criticized the view of David Hume, Adam Smith, and John Stuart Mill that currency served only as a symbol of wealth and was the least productive part of a nation's capital.

[20] He was also an early advocate of bimetallism and the remonetization of silver in order to secure a stable national currency, fearing that gold reserves in the United States were too small.

Baykedagn applied Carey's ideas on protectionism and national economic self-sufficiency to the context of Ethiopia, advocating for policies that would modernize and strengthen the country's economy.