Why did president andrew johnson have little influence over reconstruction policy during his term of office

He purchased Alaska from Russia in 1867. He defied Congress Tenure of Office act on grounds that it was unconstitutional (which He was impeached for, but the Supreme Court agreed with Johnson's reasoning) He was accommodating to the Southern states, and advocated less harsh treatment of the defeated rebels than other politicians of the time (which quickened the healing process from the Civil War) He served in the Senate after his Presidential term expired, showing further willingness to work for the public good despite his impeachment embarrassment. He protected the rights of the Executive branch against Congress' attempt to diminish it's powers.