In this beautiful blessing we ask haShem to protect and help the righteous (Tsadikim), those who are committed to pursuing the knowledge of God and following His commandments.
We ask for a special protection for them because we all need to look up to the righteous people as our role models and inspiration.
The berakha mentions two types of good people: righteous and pious (Chasidim).
Righteous are those who strictly follow God's commandments. Chasidim -pious -is a level above righteousness. Chasidim are righteous people who outdo their religious duties in one specific category of Mitzvot: Chesed. 'Chesed' means kindness, and includes the practice of everything we do for other people: visiting the sick, comforting the mourners and of course helping widows, orphans and people in need.
While 'excess' in ritual areas might be counterproductive or a symptom of arrogance, in the area of Chesed is unquestionable and noble.
It is important to notice that anyone can be a righteous or a pious Jew. Depending exclusively on one's actions and motives. And because it depends also on motives, the only One qualified to identify who is a real Tsadik is God Almighty. That is why we ask Him to protect the real Tsadikim and inspire us to follow their footsteps. vesim chelkenu 'imahem.
Maimonides explains that to increase, so to speak, God's awareness of us (hashgacha peratit), we must increase our awareness of God. The first step to become a Tsadik is having God Almighty in your mind (shiviti haShem). And the more you think about God Almighty, the more He will 'care' about you, and vice versa.