Do melee spell attacks with a range of touch bypass armor?

Question

Short version: Do melee spell attacks take into account armor when the range is Touch?

Longer version: Assuming a prepare an Inflict Wounds (PHB253) spell, that has the following properties:

Range: Touch
Description: Make a melee spell attack against a creature you can reach. On a hit [..]

Assuming that the opponent that I choose as a target has a total 15AC:

What should my attack roll be to successfully hit? 15 (the whole above) or 12 (since just touching, armor offers no protection)?

Was about to add an answer, but this does indeed look like a duplicate. You may be thinking of earlier editions which included the concept of a "Touch AC", but see duplicate question for 5th edition answer. — PJRZ, Jul 30 '18 at 16:00
Did not even remember the name "Touch AC", thought it was a given. This however pretty much sums it up, on to homebrewing the rule back in! — Nick Andriopoulos, Jul 31 '18 at 12:31

score 5 · Accepted Answer · edited Jun 16 '20 at 10:23

It's 15, the whole above

In 5e, armor might protect you from spells. Armor Class (AC) protects you from all attacks, as the PHB says:

Armor Class (AC). Armor protects its wearer from attacks.

Also, Jeremy Crawford, the lead game designer, explicitly said that so-called "melee spell attacks" were stoppable by armor.

Keep in mind that "attack" is a game term. For more details, see What counts as an attack?