Donald Trump has warned "we are on the brink of World War Three" as he blamed President Joe Biden for Iran-backed militants killing three American soldiers and wounding dozens more in Jordan.
The former President hit out at the Biden administration after a drone strike on a remote outpost known as Tower 22 near Jordan’s northeastern border with Syria.
Mr Biden is facing piling political pressure to directly attack Iran in response but he is reluctant to do so out of fear of igniting a broader war.
Mr Trump wrote on Sunday: “This brazen attack on the United States is yet another horrific and tragic consequence of Joe Biden's weakness and surrender.
"This attack would NEVER have happened if I was President, not even a chance - Just like the Iranian-backed Hamas attack on Israel would never have happened, the War in Ukraine would never have happened, and we would right now have Peace throughout the World. Instead, we are on the brink of World War 3."
Mr Trump has falsely claimed several times that there were no US troops killed in Afghanistan for 18 months during his presidency. This has been debunked.
American forces in the Middle East have been attacked more than 150 times by Iran-backed forces in Iraq, Syria, Jordan and off the coast of Yemen since the Israel-Hamas war erupted in October.
The deaths mark the first US fatalities in months of strikes against American forces across the Middle East by Iranian-backed militias.
Mr Biden has said the United States would respond to the attack, without giving any more details.
Experts have said Mr Biden’s response could range from targeting Iranian forces inside Iran or a more cautious retaliatory attack against the Iran-backed militants who were responsible.
Meanwhile Republicans have accused the president of letting American forces become sitting ducks, waiting for the day when a drone or missile would evade base defences.
Republican U.S. Senator Tom Cotton, a Donald Trump supporter, said: "The only answer to these attacks must be devastating military retaliation against Iran's terrorist forces, both in Iran and across the Middle East."
One Democrat also voiced concern that Biden's strategy of containing the Israel-Hamas conflict to Gaza was failing.
"As we see now, it is spiralling out of control. It's beginning to emerge as a regional war, and unfortunately the United States and our troops are in harm's way," Democratic Representative Barbara Lee said, renewing calls for a ceasefire in the Israel-Palestinian war.
The United States has struck Iranian-linked targets outside of Iran in recent months.
In November, the US military said it struck a facility used by Iran's Revolutionary Guard Corps.
