Telescope?
Besides, don’t we have radio directional capabilities to determine where it’s coming from?
When's the last time you used a radio with directional capabilities? Radios don't work that way. I'm sure the Navy has RDF capabilities on many of its ships, but it would be a separate device which would have to be activated, and would take a little time to identify a direction.
Have you seen those amazing pictures from the Hubble telescope? Impressive civilian technology used to support scientific progress. Now that we know the technology exists, is there any reason to doubt that the military has made full use of it? Of course not. Our spy satellites are probably just equivalent to the Hubble but pointed groundward.
Now think about the GPS system with its near synchronous satellites. Do we use RDF, Radio Direction Finding, to pinpoint a receiver's position on Earth? No. The receiver compares synchronized signals from various satellites and computes position from the observed differences in arrival time at the receiver.
Now let's ask ourselves, "Would it be useful militarily to have a system whereby the military can pinpoint the location of radio stations on Earth? The obvious answer is "yes".
Now we ask ourselves, would the technology to do so be prohibitively expensive? For the U.S government? Heck, no!
So what does the system have to look like? It looks surprisingly like the GPS system. It may even use the same satellites.
Want to pinpoint the location of a transmitter operating at 200MHz? Program all the GPS satellites to monitor a narrow band around that frequency and record the transmissions with high fidelity. On command from the ground, download the high fidelity recording of the transmission from each satellite along with the exact time that the signal was received.
Then compare the recordings to identify identical transients in each recording and note the exact time that said transient was recorded at several satellites. The same algorithm used by a receiver to calculate its position using GPS will then enable the military to calculate the position of the radio transmitter.
In case this system hasn't been invented or patented, I hereby claim rights as its inventor with the intention to enrich myself consistent with its commercial value.