With US officials having already committed to keeping troops inside Syria more or less forever, Secretary of State Mike Pompeo set the same standard for the provision of any reconstruction aid in Syria, the expulsion of Iranian and Iranian-backed forces.
Pompeo says Syria’s government “bears responsibility” for the Iranians being there, and that the onus is on them to expel all of them before any costruction came happen.
The “Iranian-backed” forces standard is extremely broad, as the US can, and at times haas, argued that almost everyone on the side of the Syrian government is effectively an Iranian proxy. This means there is unlikely to ever be a case where US officials are satisfied that all Iranians and Iranian-backed forces are gone.
Effectively this rules out US involvement in post-war reconstruction in Syria, which probably isn’t a surprising fact, as the US wanted regime change from the start, and didn’t get it. It’s not clear if this rules out aid for the Syrian Kurds in reconstruction of the vast territory they control.