It struck me this morning what this part of the Lord's prayer is about.
For my entire lifetime until now, I thought it meant that somehow my prayer was facilitating God's will being done.
This week, however, I have been thinking a good bit about God's sovereignty. This morning the light bulb finally went on about this part of the prayer. It is an expression of one's submission to God's will. Because God's will will be done, whatever I think or I pray. That's not the issue being addressed, whether it will be done or not. The issue is whether I will acknowledge him as truly, thoroughly, absolutely God and will therefore acknowledge my submission to his will.