Please. Anyone thinking the confederates posed a threat is not being serious. Lincoln trampled on all sorts of constitutional matters in his efforts to impose his will.
As with most Liberals, and really, that is what he was for his day, he picked and chose what he wanted to support and ignored things he didn't like.
Your second sentence contradicts your first, FRiend.
If the Confederacy were truly "no threat", then Lincoln would have no need to "trample" anything.
In actual fact, in early 1861 the Confederacy posed an existential threat to the United States, not only in the Deep South which declared secession over slavery alone.
But also in the Upper South, which at first refused to secede over slavery alone, but loudly threatened to secede if the Union attempted any "oppression" of the Deep South.
So, when push came to shove, the Upper South, beginning with Virginia, declared Lincoln's response to Fort Sumter an act of "oppression" and so declared its own secession, plus joined the Confederacy's declared war on the United States.
But even then, the Upper South did not secede unanimously, with huge areas of each state remaining loyal Unionists -- western Virginia (17% Union troops), eastern Tennessee (27% Union troops), western North Carolina (7% Union), north-western Arkansas (19% Union).
These areas contributed significant support and soldiers to the Union army, as did notably Louisiana.
But in Lincoln mind, the Union would be won or lost in the Border States -- Kentucky, Missouri and Maryland.
All were majority Unionists, but with powerful pro-Confederate minorities, including the governors of Missouri and Kentucky.
They were also assaulted militarily by Confederates, Missouri beginning in early 1861, making the Confederacy an existential threat to states which were majority Unionists.
Further, the Confederacy in 1861 immediately invaded Union territories of Oklahoma and New Mexico / Arizona.
And over the course of the war, Confederate forces invaded every Union state & territory within their reach, including Maryland, Pennsylvania, Ohio, Indiana, Kentucky, Missouri, Kansas, Oklahoma, New Mexico / Arizona, threatening Illinois and Colorado.
Confederate guerillas also attacked targets in New Hampshire, Colorado and California.
And in most cases of Confederate forces in Union states, they behaved in ways that even General Sherman did not emulate.
So any suggestion that the Confederacy was "no threat" is just ridiculous.
From Day One the Confederacy was an existential threat to the United States, a fact well demonstrated by the four years it took to defeat them.