USA provides extensive engineering support and technology transfer for Ukraine's domestic development of long-range missiles. Basically everything short of just giving them Tomahawks. Ukraine's defense industry capabilities didn't develop so rapidly for no reason.
And the quality of targeting is almost entirely because of extensive USA intelligence sharing:
> According to American and Ukrainian officials familiar with the operations:
> Ukraine selects targets, although American intelligence reportedly also helps identify high-priority facilities.
> The US identifies vulnerabilities at Russian energy installations.
> American intelligence assists with mission planning, including routes, altitude, and timing to help Ukrainian drones evade Russian air defenses.
> US involvement extends across multiple stages of planning, according to three people familiar with the operations.
https://www.reuters.com/world/europe/us-intelligence-helps-u...
And the quality of targeting is almost entirely because of extensive USA intelligence sharing:
> According to American and Ukrainian officials familiar with the operations:
> Ukraine selects targets, although American intelligence reportedly also helps identify high-priority facilities.
> The US identifies vulnerabilities at Russian energy installations.
> American intelligence assists with mission planning, including routes, altitude, and timing to help Ukrainian drones evade Russian air defenses.
> US involvement extends across multiple stages of planning, according to three people familiar with the operations.
https://www.reuters.com/world/europe/us-intelligence-helps-u...