“Texas could exist without U.S., but U.S. can’t exist without Texas” (Sam Houston)

Sam Houston favored the annexation of Texas to the United States. Nevertheless, in 1844, he wrote the following to General Andrew Jackson: “Texas, with peace, could exist without the United States, but the United States can not, without great hazard to the security of their institutions, exist without Texas.”
 
The statement has become a Texas classic, especially for those who believe that Texas is a “like a whole other country.”

 
Google Books
Life and Select Literary Remains of Sam Houston of Texas
by William Carey Crane
Philadelphia: J. B. Lippincott & Co.
1884
Pg. 370:
LETTER TO GEN. ANDREW JACKSON.
WASHINGTON [-on-the-Brazos—ed.], February 16, 1844.

VENERATED FRIEND:—
(...)
It is natural to suppose that the subject of the annexation of Texas to the United States has commanded the most profound deliberation of which I am capable.(...) So far as I am concerned, or my hearty co-operation required, I am determined upon immediate annexation to the United States.
 
It is no tthe result of feeling, nor can I believe that the measure would be as advantageous to Texas if she had permanent peace, as it is indispensably necessary to the United States. Texas, with peace, could exist without the United States, but the United States can not, without great hazard to the security of their institutions, exist without Texas.
(...)
Truly your friend,
SAM HOUSTON