"It is easier to start a war than to end it” is usually credited to Colombian novelist Gabriel García Márquez (1927-2014). He wrote in his book, One Hundred Years of Solitude (1967):

“‘You won’t see me,’ Colonel Aureliano Buendía said. ‘Put your shoes and help me get this shitty war over with.’ When he said it he did not know that it was easier to start a war than to end one.”

However, the saying has been cited in print since at least 1897. “King George has discovered by this time that it is much easier to start a great war than to stop it” was printed in the Harrisburg (PA) Star-Independent on May 14, 1897.  “It is easier to start a war than to stop it, as the Greeks have discovered” was printed in The Repository (Canton, OH) on May 23, 1897.


Wikiquote: Gabriel García Márquez
Gabriel José García Márquez (6 March 1927 – 17 April 2014) was a Colombian novelist, journalist and activist. He was awarded the 1982 Nobel Prize for Literature.
(...)
One Hundred Years of Solitude (1967)
Cien años de soledad as translated by Gregory Rabassa (1970), Harper Perennial Modern Classics ISBN 0060883286
At dawn, worn out by the tormented vigil, he appeared in the cell an hour before the execution. “The farce is over, old friend,” he said to Colonel Gerineldo Marquez. “Let’s get out of here before the mosquitos in here execute you.” Colonel Gerineldo Marquez could not express the disdain that was inspired in him by that attitude.
“No, Aureliano,” he replied. “I’d rather be dead than see you changed into a tyrant.”
“You won’t see me,” Colonel Aureliano Buendía said. “Put your shoes and help me get this shitty war over with.”
When he said it he did not know that it was easier to start a war than to end one.
p. 169

Newspapers.com
14 May 1897, Harrisburg (PA) Star-Independent, pg. 4, col. 2:
King George has discovered by this time that it is much easier to start a great war than to stop it.

23 May 1897, The Repository (Canton, OH), pg. 12, col. 2:
AS TO STARTING AND STOPPING.
Massillon Independent.—(...) “It is easier to start a war than to stop it, as the Greeks have discovered.”

Newspapers.com
2 June 1897, Scranton (PA) , pg. 4, col. 2:
The European Powers have found that it is easier to start a war than to end one.

Newspapers.com
27 August 1939, The Enquirer and The Evening News (Battle Creek, MI), “Post Quips” by Glenn Post, pg. 4, col. 6:
Dear Mr. Hitler: It is easier not to start a war than to stop one.

Newspapers.com
27 January 1951, Boston (MA) Daily Globe, pg. 22, col. 5:
Easier to Start a War Than Stop It
By MARQUIS CHILDS
WASHINGTON—As history has shown again and again, it is always easier to start wars than to stop them.

18 July 1951, The Evening Star (Washington, DC), pg. 9, col. 3:
It’s Easier to Start a War Than End It
By David M. Nichol
BERLIN.—Starting a war is a cinch compared with the problems of ending one.

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It’s easier to start a war than to finish one… by Peggy Noonan http://online.wsj.com/article/SB10001424052748703818204576206874121726838.html #TheOpinionPage
12:42 PM · Mar 18, 2011·Twitter for Mac

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It’s much easier to start a war than to finish one—
@ariannahuff on the troop drawdown http://huff.to/kZB59J
8:48 PM · Jun 20, 2011·The Huffington Post

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English Literature
February 23, 2019 ·
“It is easier to start a war than to end it.”
― Gabriel Garcia Marquez