Final answer:
Lincoln meant that all laws should be executed to prevent the government from collapsing.
Step-by-step explanation:
When Lincoln asked, "Are all the laws, but one, to go unexecuted, and the goverment itself go to pieces, least that one be violated?", he was referring to the importance of upholding the laws in order to maintain the stability and functioning of the government. He believed that if one law was allowed to be violated, it could lead to a breakdown of the entire system. Lincoln's statement reflects his commitment to preserving the Union and enforcing the laws of the land.