Lincoln closes by saying that he hopes the Congress will agree with his actions, that they were the best that he could do given the circumstances that he had been dealt, and Lincoln wants to make it clear that before he had even taken office, seven southern states had seceded from the Union, and therefore, considered themselves outside of the powers of the national government. He then goes on to give examples of how these states were using federal property in order to prepare for war against the United States.
Simply stated, the southern states had declared themselves independent of the United States, had joined what they called the Confederate States of America and were actively seeking foreign allies to help them in their cause.
>https://abrahamlincoln.quora.com/Message-to-Congress-July-4-1861