This is a speech by A. Lincoln. I have edited it for length. Source is posted so that you may read the entire speech if you desire.

*************************
War of the Rebellion: Serial 122 Page 0311 UNION AUTHORITIES.

FELLOW-CITIZENS OF THE SENATE AND HOUSE OF REPRESENTATIVES
———
At the beginning of the present Presidential term, four months ago, the functions of the Federal Government were found to be generally suspended within the several States of South Carolina, Georgia, Alabama, Mississippi, Louisiana, and Florida, excepting only those of the Post-Office Department.

Page 312
In accordance with this purpose an ordinance had been adopted in each of these States declaring the States, respectively, to be separated from the National Union. A formula for instituting a combined government of these States had been promulgated, and this illegal organization, in the character of Confederate States, was already invoking recognition, aid, and intervention from foreign powers. ————-

It sought only to hold the public places and property not already wrested from the Government and to collect the revenue, relying for the rest on time,

Page 319
Again, if one State may secede, so may another; and when all shall have seceded none is left to pay the debts. Is this quite just to creditors? Did we notify them of this sage view of ours when we borrowed their money? If we now recognize this doctrine by allowing the seceders to go in peace, it is difficult to see what we can do if others choose to go, or to extort terms upon which they will promise to remain.

Page 321

It was with the deepest regret that the Executive found the duty of employing the war power, in defense of the Government, forced upon him. (Yeah right, we have already proven that to be a lie.)

Page 322
ABRAHAM LINCOLN.
JULY 4, 1861.

So we see Lincoln wanted to preserve the Union for the purpose of collecting revenue.