Happy INDEPENDENCE Day!

Why do we say Happy 4th of July?

The 4th of July.

We've even dropped July and shortened it to "The 4th"

Its name is Independence Day.

We don't say Merry 25th of December.

Merry 25th.

Happy 14th of February, honey.  I love you.

So why has this day lost its name?

I don't get it.

Peeve.