Why did general Lee's invasion on Maryland fail in 1862?

General Robert E. Lee's invasion of Maryland in 1862 failed primarily due to a combination of logistical challenges and the Union's strategic advantages. The Confederate Army was hampered by supply issues and the loss of critical orders, which were discovered by Union forces. Additionally, the Union Army, under General George McClellan, was able to capitalize on Lee's divided forces and ultimately engage them at the Battle of Antietam, resulting in a costly stalemate that halted Lee's advance. The failure to secure a decisive victory in Maryland diminished the Confederacy's hopes of gaining recognition and support from European powers.