Watch o’er all those who guard our coasts.
Protect them from the raging seas
And give them light and life and peace.
Grant them from Thy great throne above
The shield and shelter of Thy love.
It is the same tune as Eternal Father, Strong to Save (the Navy Hymn), and can be added in to that hymn or substituted for stanza 1 (as long as you are not going to offend any Navymen!).
On a personal note, Carolyn, this is for you!