Clay was again chosen Speaker on the meeting of the Sixteenth Congress and continued to be its leading member, frequently criticising Mon roe's administration in hard terms. This was the period of the great contest over the admission of Missouri.
Clay, though not the author of the Missouri Compromise of 1820, did bring about the com promise of the next year, by which it was agreed that should be admitted (without re striction as to slavery) on her promise not to prevent citizens of other States from settling within her borders. Declining to the following Congress, he did not appear in active politics again until 1823, when he reoccupied the Speaker's chair. In the election of 1824 he was a candidate for the Presidency, together with Crawford, Jackson, and Adams.
The Electoral College failing to elect, the choice between the three highest candidates fell to the House, where Clay, who had come fourth and was thus not eligible for elec tion, east his strength for Adams. Soon after the latte•'s inauguration, Clay was appoint ed Secretary of State—a fact which gave point to the cry of 'Bargain and corruption; which, though baseless, and again and again re fitted, never ceased to injure him in his political career. Pis relations with Adams were de nounced by John Randolph as the "combination of the Puritan with the blaekleg," language which provoked a challenge from Clay; but neither party was wounded in the duel that ensued, Randolph refusing to fire at his adversary the second time. The Secretaryship of State, for me•ly regarded as the stepping-stone to the Presidency, proved an obstacle to Clay, and though lie made an excellent officer, lie regretted his long absence from Congress, where he could always lead. A strong opponent of General Jack son as a candidate for the Presidency, lie retired with Mr. Adams after the latte•'s defeat in 1829. TWO years later lie was elected to the Sen ate. Here, in the difficult role of Senator and Presidential candidate, lie was prominent in his advocacy of the protective syst ern, which he (11'1)1)0 unreasonably, but successfnlly, the 'American system.' Unanimon%ly nominated by the Whigs, Clay was overwhelmingly defeated by .)aekson
(1832), largely on account of his tariff ideas, and his unwise choice, as a party issue, of the defense of the National Bank. When the NnIli tication controversy came up, Clay's compromise of 1833 prevented a resort to arms by satisfying South Carolina with regard to the reduction of the obnoxious tariff and rendering the Force Bill unnecessary. In the subsequent anti-slavery agit:ition he occupied a moderate position. but lost few opportunities of opposing the adminis tration of Jackson. Throughout this period of his career Clay shared the honors of the Senate in its time of meridian glory with Daniel Web ster, John C. Calhoun, and T. H. Benton.
During Van Buren's Presidency, Clay unsuc cessfully opposed the administration measure of an independent treasury system, desiring in its stead the establishment of a national bank; but after Harrison's election he procured its repeal, the apparent victory proving, however, far from permanent. In the election of 1840 he was cha grined at not receiving the Whig nomination. but supported Harrison, and after the latter's death endeoN ored to carry out the Whig policy, espe cially with regard to rechartering a national hank. In this attempt he was thwarted by the vacillation and ambition of President Tyler.
After the breach between the 'Tyler men' and the `Clay Whigs' became apparently irreconcil able, Clay resigned his seat in the Senate and re tired to private life ( 1S42). He was nominated for President in the campaign of 1844, and defeated by James K. Polk. Clay's defeat was due to his injudicious writing of letters, in which he did not take a stand upon the question of the ad mission of Texas that satisfied the more extreme opponents of slavery. He was again and for the last time spoken of as an aspirant for Presi dential honors in the convention that nominated General Taylor in 1848. Meanwhile he had on the whole lived in retirement, hut had watched with anxiety the growth of friction between North and South consequent upon the Mexican War. In 1848 he was reelected to the United States Senate.