A standing political proof-text. The chapter itself defines what it means, three verses earlier.
Quick answer
What lifts a nation is righteousness, and this book has already said what righteousness looks like in public: honest dealing and mercy to the poor.
Read both lines
The claim is broad and the verse names no nation, which matters. It is a general observation about what makes a people flourish or corrode, offered in a book of general observations, and the terms are the ones Proverbs has been defining for thirteen chapters. Righteousness here is not a religious identity but right dealing: accurate scales (11:1), truthful witness (14:25), and mercy to the needy. The second line's key word is unusual and the NKJV footnotes it as shame or disgrace, so what sin does to a people is degrade them in a way everyone can see.
What it does not mean
This verse is quoted constantly in political argument, and it will not carry most of what it is asked to carry. It does not identify any modern nation with Israel, it does not endorse a party, a platform, or a program, and it does not license the claim that a particular election or policy is what God meant by righteousness. The strongest guard is in the chapter itself. Three verses earlier, 14:31 says that oppressing the poor reproaches God and that honoring Him is having mercy on the needy. Whatever national righteousness means in verse 34, it cannot mean less than what verse 31 just said it means. Any use of this verse that leaves the poor worse off has been argued against by its own chapter.
Christians disagree in good faith about which policies serve those ends, and Grace Answers does not adjudicate that here. What the verse settles is the direction, not the ballot.
Related: Proverbs 14:31 · Proverbs 11:1 · Proverbs 29:4 · Micah 6:8
New King James Version®, Copyright © 1982, Thomas Nelson. All rights reserved. Full copyright information. Scripture provided by API.Bible.
Go Deeper
If this verse has been used to put weight on you that it was never carrying, ask about it directly.