*Russia accused of intimidating US consulate staff [Who are Russians] with Ukraine war spying charges.*
What Shonov is accused of — relaying non-secret information picked up from the public — is a normal part of the work of staff of diplomatic organizations.
The US consulate would have trouble functioning without these employees. But it can't tolerate this repression.
The US could not morally respond by threatening the American citizens and other non-Russians who work for Russian consulates in the US. What it could legitimately do is restrict how many local employees the Russian consulates could employ. If the intimidation goes so far that the US consulates find it necessary to stop employing local staff, the US should bar Russian consulates from hiring any local employees.