Jim Michaels

USA TODAY

WASHINGTON — The Pentagon said Monday that last week’s U.S. missile strike on an air base in Syria destroyed or damaged 20 Syrian warplanes — 20% of that country's operational military aircraft — and blew up much of the base's fuel supply.

The announcement comes after Syrian warplanes resumed using the base Saturday, raising questions about why the runway wasn’t cratered so it couldn't be used.

The Syrian military won’t be able to sustain operations at the Shayrat air base because of damage to its fuel supplies and other equipment, the Pentagon said.

“The Syrian government has lost the ability to refuel or rearm aircraft at Shayrat airfield," Defense Secretary Jim Mattis said in a statement.

The Shayrat base was targeted because Syria allegedly launched chemical weapons from there April 4 that devastated the town of Khan Sheikhoun, leaving 86 people dead, including dozens of children.

The U.S. strike early Friday, which involved 59 Tomahawk cruise missiles fired from two warships, was not aimed at personnel, and Russian forces in Syria supporting the government were warned of the attack. The Syrian military said at least nine people were killed and several more wounded by the U.S. strike.

The U.S. attack ordered by the Trump administration avoided targeting chemical stockpiles at the base to avoid explosions that could release deadly toxins into the air, the Pentagon said.

The Trump administration have described the strikes as being designed to send a message to the regime of Syrian President Bashar Assad, but were not aimed at forcing him from power.

“The Syrian government would be ill-advised ever again to use chemical weapons,” Mattis said in the statement.

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