Which could best serve as the theme of a story?

How would you write "the fourth of july? " the 4th of july or the fourth of july? are they both grammatically correct?

It is true that prior to 1914 the united states often had been disturbed by events in other continents. we had even engaged in two wars with european nations and in a number of undeclared wars in the west indies, in the mediterranean and in the pacific for the maintenance of american rights and for the principles of peaceful commerce. but in no case had a serious threat been raised against our national safety or our continued independence. what is the theme of this excerpt? a. the responsibility for americans to avoid involvement in war.b. america’s history of international involvement.c. a new kind of threat to american security.d. america’s history as a peaceful nation.

When first i engaged in this work, i resolved to leave neither words nor things unexamined, and myself with a prospect of the hours which i should revel away in feasts of literature . . –preface to a dictionary of the english language, samuel johnson what is the connotation of the word revel in this passage?