Well I think it's safe to say that the Southern people were certainly inclined to rebel. But they did lack the power, didn't they?
The secession of a state from the Union depends on the will of the people of such state. The people alone as we have already seen, hold the power to alter their constitution...But in any manner by which a secession is to take place, nothing is more certain that the act should be deliberate, clear, and unequivocal. To withdraw from the Union is a solemn, serious act. Whenever it may appear expedient to the people of a state, it must be manifest in a direct and unequivocal manner."
There is a reason why I inserted the ellipses in your quote; it's because you left out a whole section of the paragraph. That part reads, "The state legislatures have only to perform certain organical operations in respect to it. To withdraw from the Union comes not within the general scope of their delegated authority. There must be an express provision to that effect inserted in the state constitutions. This is not at present the case with any of them, and it would perhaps be impolitic to confide it to them. A matter so momentous, ought not to be entrusted to those who would have it in their power to exercise it lightly and precipitately upon sudden dissatisfaction, or causeless jealousy, perhaps against the interests and the wishes of a majority of their constituents." So if, in Rawle's opinion, the state legislatures lacked the constitutional authority to secede without an addition to their constitution then when were those provisions added and what is the wording?
So do you agree or disagree with Lincoln here? Do people have the right to self government or not?
The secession of a state from the Union depends on the will of the people of such state
This is the main point, a theme taken directly from the Declaration of Independence. The part about the legislatures adding this to their constitutions is something he is strongly recommending (because he believes, as you see, that this right will be abused). Their is no law anywhere saying that such is a requirement to leave.