"'Then when the king's edict is proclaimed throughout all his vast realm, all the women will respect their husbands, from the least to the greatest.'" NIV translation
Memucan must have had problems at home with his own marriage as that is the focus of his reasoning. These men (who do not know of God) are preparing a law to protect marriages which were designed by God. They do not know that, without God at the center, a marriage cannot be successful as only God has the wisdom to unite two people.
"The king and his nobles were pleased with this advice, so the king did as Memucan proposed. He sent dispatches to all parts of the kingdom, to each province in its own script and to each people in its own language, proclaiming in each people's tongue that every man should be ruler over his own household." NIV translation
The king issued the proclamation and we will see how God used that to protect His people.
We must stop here and contrast this pagan idea of the man being the "ruler" of the house with what God says about the husband. This concept of being the ruler is not exactly what God wants for the Christian home.
As we see in Ephesians 5, the husband is the head just like Christ is the head of the church. Christ rules over His church with love instead of harsh decrees.