You are taking 1 Thessalonians 5:3 completely out of context. It has absolutely nothing to do with the world saying peace and safety in terms of the world being a peaceful and safe place.
When Paul indicated that they will say "peace and safety" and then sudden destruction would come upon them, the context is about those who think they are SPIRITUALLY at peace and safe when in reality they are SPIRITUALLY sleeping and unaware of their SPIRITUAL status of being in SPIRITUAL darkness.
1 Thessalonians 5:1 But of the times and the seasons, brethren, ye have no need that I write unto you.
2 For yourselves know perfectly that the day of the Lord so cometh as a thief in the night. 3 For when they shall say, Peace and safety; then sudden destruction cometh upon them, as travail upon a woman with child; and they shall not escape. 4 But ye, brethren, are not in darkness, that that day should overtake you as a thief. 5 Ye are all the children of light, and the children of the day: we are not of the night, nor of darkness. 6 Therefore let us not sleep, as do others; but let us watch and be sober.
Notice how Paul contrasts believers who are not in darkness spiritually and are instead "the children of light" with unbelievers who are in spiritual darkness. And he said "let us not sleep, as do others; but les us watch and be sober". The others, which are unbelievers, are spiritually sleeping and not watching what is going on spiritually which results in them being in spiritual darkness. They are deceived and think that they are at peace and are safe spiritually, but they are not. Because of their rejection of Christ they are not at peace and safe spiritually at all. If they don't repent before Christ comes then they will have "sudden destruction" come down upon them from which "they shall not escape".