Fair call on the funding, I know the US was paying for the French military's involvement for years. Still, by active support I meant troops on the ground, which happened significantly later.

Who resumed the fighting does matter, as even though Diem refused the 1956 reunification elections that didn't justify resorting to an armed insurgency by the North. It's also not ambiguous, Hanoi's 15th plenum officially authorised that insurgency in 1959 and formed groups 559 and 759, and later the NLF (Viet Cong).

They were already killing hundreds of innocent South Vietnamese village chiefs, teachers, and officials by the late 1950s, trying to create a local insurgency and insurrection. That's what the US got involved with to oppose, and I really can't say it was a morally wrong decision at the time. Hanoi had the option of sticking with diplomacy and chose to send guerrillas south instead. You're giving only the US agency here.