It's time for the United States to hold Iran accountable.

U.S. forces have been instructed to take all measures needed to protect American interests in Syria, including military measures, as part of an effort that comes after top officials in the Trump administration assessed that Iran is deliberately probing American weaknesses and reactions on the Syrian battlefield, according to senior Trump administration officials who spoke to the Washington Free Beacon.

Iran-backed forces, including Hezbollah, have already initiated multiple encounters with the United States by violating agreements worked out between Washington and Moscow aimed at preventing the various factions targeting ISIS inside Syria from coming into conflict. This is part of a campaign that analysts inside and outside the White House believe is aimed at testing the Trump administration's resolve, sources said.

"That was very clearly a process of the Iranians and Hezbollah and [the] Syrian regime probing and testing our limits, and testing how much we were willing to do," one senior Trump administration official said. "In every case, it was a matter of them testing and probing, and us responding by defending ourselves."

These clashes were the result of pro-Syrian regime forces, including Iran and Hezbollah, "violating a de-confliction measure that had been worked out with the Russians," the official said. "The forces violated the measure."

The Trump administration has instructed U.S. forces to respond to Iranian attacks with force if necessary.

"What they found out very quickly," said the official, was "us responding by defending ourselves. What was established was that we're determined to defend ourselves."

This defensive action is being implemented at the same time the Trump administration turns its attention to the Iranian Revolutionary Guards Corps (IRGC), the Islamic Republic's paramilitary force that coordinates operations in Syria and other warzones.

Trump administration officials view the IRGC as being part of "every malignant protrusion of the Iranian regime," according to one administration official, who said the White House is dually focused on choking off this force.

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