Editing Ambrose Burnside (section)

===Antietam===
[[File:Burnside's Bridge, Sharpsburg, MD.jpg|thumb|[[Burnside's Bridge]] at Antietam in 2023]]
Burnside was given command of the Right Wing of the Army of the Potomac (the [[I Corps (Union Army)|I Corps]] and his own IX Corps) at the start of the [[Maryland Campaign]] for the [[Battle of South Mountain]], but McClellan separated the two corps at the [[Battle of Antietam]], placing them on opposite ends of the Union battle line and returning Burnside to command of just the IX Corps. Burnside implicitly refused to give up his authority and acted as though the corps commander was first Maj. Gen. [[Jesse L. Reno]] (killed at South Mountain) and then Brig. Gen. [[Jacob Dolson Cox|Jacob D. Cox]], funneling orders through them to the corps. This cumbersome arrangement contributed to his slowness in attacking and crossing what is now called [[Burnside's Bridge]] on the southern flank of the Union line.<ref>Bailey, pp. 120–21.</ref>

Burnside did not perform an adequate reconnaissance of the area, and he did not take advantage of several easy fording sites out of range of the enemy; his troops were forced into repeated assaults across the narrow bridge, which was dominated by Confederate sharpshooters on the high ground. By noon, McClellan was losing patience. He sent a succession of couriers to motivate Burnside to move forward, ordering one aide, "Tell him if it costs 10,000 men he must go now." He further increased the pressure by sending his inspector general to confront Burnside, who reacted indignantly: "McClellan appears to think I am not trying my best to carry this bridge; you are the third or fourth one who has been to me this morning with similar orders."<ref>Sears, pp. 264–65.</ref> The IX Corps eventually broke through, but the delay allowed Maj. Gen. [[A. P. Hill]]'s [[Confederate States Army|Confederate]] division to come up from [[Harpers Ferry, West Virginia|Harpers Ferry]] and repulse the Union breakthrough. McClellan refused Burnside's requests for reinforcements, and the battle ended in a tactical stalemate.<ref>Bailey, pp. 126–39.</ref>