The Russian president said that Moscow would respond with "comprehensive measures" after the Pentagon test-fired a non-nuclear cruise missile.
Moscow is studying the remains of Tomahawk rockets to exploit their weaknesses.
The world's top two military powers may be on a collision course in Syria.
The U.S., Russia and China are all looking to surpass each other with military innovations such as missiles and drones that use artificial intelligence.
Trump has learned that the presidency can be an incredibly frustrating job.
Moscow called tough U.S. talk and action on the Syrian regime "flexing muscles" and "baring teeth."
The president was presented with a plan that would have included a strike on Syrian President Bashar al-Assad's palace.
Moscow had its S-400 missile system in range of the strike.
Its payload, range and navigation benefits explained.