As tensions between the United States and North Korea intensify, President Donald Trump on Friday took to Twitter (TWTR) - Get Report to announce that the military is "locked and loaded," prepared to respond if North Korea "acts unwisely."

Although it can't be known if military action will be needed now, Trump said he hopes North Korea's supreme leader Kim Jong Un finds "another path," as a missile-driven war would be very costly.

The tension between the two countries was enough to send some aerospace and defense stocks soaring Friday. Would companies like Boeing (BA) - Get Report , Lockheed Martin (LMT) - Get Report , Raytheon (RTN) - Get Report and Northrup Grumman (NOC) - Get Report reach fresh highs if conflict with North Korea comes to a head?

The threat of war also sent investors fleeing to safe haven assets, weighing on the stock market and sending volatility to new records. The cost of war is enormous in every sense - but what does that translate to in dollars?

We take a look back at the 10 most expensive wars in U.S. history with price adjusted for inflation.

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Editors' pick: Originally published August 11.