Growing up I went to a bais yaacov school and we always said the pledge of allegiance in the afternoon in english class and we stood and put our hand to our heart.
I know people who put up an american flag on the fourth of July and Memorial day. Also in my neighborhood we have a parade on Memorial day and I know frum people who join in marching and watching and waving flags. It is to show the goyim that even though we are jewish we still support the country we live in.
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