Election to Salvation is unconditional b before the World because its of Divine Origin, the Eternal Purpose and Mind of God before the world began,
He Created according to His Purpose the elect as vessels of mercy Rom 9:20-23
20 Nay but, O man, who art thou that repliest against God? Shall the thing formed say to him that formed it, Why hast thou made me thus?
21 Hath not the potter power over the clay, of the same lump to make one vessel unto honour, and another unto dishonour?
22 What if God, willing to shew his wrath, and to make his power known, endured with much longsuffering the vessels of wrath fitted to destruction:
23 And that he might make known the riches of his glory on the vessels of mercy, which he had afore prepared unto glory,
How did He afore prepared them unto Glory ? By Election, by choosing them in Christ before the world began Eph 1:4
These are the Elect according to the foreknowledge of God the Father as Peter writes 1 Pet 1:2
2 Elect according to the foreknowledge of God the Father, through sanctification of the Spirit, unto obedience and sprinkling of the blood of Jesus Christ: Grace unto you, and peace, be multiplied.
This word foreknowledge should not be divorced from its counterpart foreordination as set forth here 1 Pet 1:20
20 Who verily was foreordained before the foundation of the world, but was manifest in these last times for you,
And the word for foreknowledge in 1 Pet 1:2 is adjoined with Gods determinate counsel in Acts 2:23
23 Him, being delivered by the determinate counsel and foreknowledge of God, ye have taken, and by wicked hands have crucified and slain:
The word and is a copulative conjunction !