To call the agreement between President Buchanan and Governor Gist a 'treaty' is a bit of hyperbole on your part, isn't it Pea? After all treaties are approved by the senate and negotiated between soverign nations. South Carolina had not rebelled yet.
But regardless of what you call it, it was merely an agreement between Buchanan and Wiliam Gist that Buchanan would ignore requests for reinforcements if Gist would guarantee the safety of government property. And Buchanan kept his part of the bargain until Gist violated the agreement by seizing Fort Moultrie and Castle Pinkney.
Your claims that Anderson ignored or violated orders are wrong. The Secretary of War had sent Major Don Carlos Buell to Charleston in December to gague the situation. In his written instructions to Anderson, Major Buell had suggested that Anderson concentrate his command at whatever fort Anderson deemed "most proper to increase its power of resistance." Major Buell cautioned Anderson that he should do so only in the event of "tangible evidence of a desing to proceed to a hostile act" against his garrison and cautioned Anderson to "not allow the opportunity to escape."
Three days after South Carolina declared rebellion, the Secretary of War sent a cabinet directive to Anderson ordering him to "exercise sound military discretion" and to avoid "useless sacrifice" on the part of his command. In light of these instructions Anderson acted in the manner he thought best safegarded his command and secession was all the incentive necessary for Anderson to take action. After Anderson had followed his orders, Gist violated his agreement with Buchanan by seizing federal facilities. Buchanan was no longer bound by the agreement and sent reinforcements in January.
Your claims that Anderson ignored or violated orders are wrong.
"In a letter to Anderson dated 27 December 1860, Buchanan's Secretary of War John B. Floyd wrote, 'Intelligence has reached here this morning that you have abandoned Fort Moultrie, spiked your guns, burned the carriages, and gone to Fort Sumter.'
"It is not believed, because there is no order for any such movement."
In a meeting with Senators Jefferson Davis and R.M.T. Hunter, (the next day) Buchanan stated, "I call God to witness, you gentlemen, better than anybody, know that this is not only without but against my orders"
Three days after South Carolina declared (secession), the Secretary of War sent a cabinet directive to Anderson ordering him to 'exercise sound military discretion' and to avoid 'useless sacrifice' on the part of his command. In light of these instructions Anderson acted in the manner he thought best...
Which resulted in Buchanan failing to order him back, and the rebellion and resignation of some of his cabinet members.
Wrong. The agreement was that Anderson was to discontinue any efforts to improve his position, and that SC would not seize the forts.
And Buchanan kept his part of the bargain until Gist violated the agreement by seizing Fort Moultrie and Castle Pinkney.
Your opinion, and wrong again.
Fort Moultrie and Castle Pinkney were abandoned by the Union troops. Isn't seized a bit of hyperbole? They were unoccupied
After Anderson moved on the 26th, the SC governor telegraphed both the commissioners and the President, strongly requesting that Anderson move back. Buchanan failed to honor the "peace agreement". South Carolina did nothing to violate the agreement, because the agreement was for peace, and peace was occuring in the harbor.