<p>➀ The US Air Traffic Control Association criticized the slow progress in resolving air traffic control system issues, highlighting the lack of a comprehensive plan since 1957;</p><p>➁ Despite congressional acts (1957 Airways Modernization Act and 1958 Federal Aviation Act) and allocated funds, no effective system plan was developed over three years;</p><p>➂ The root issue stems from failure to clearly define the problem, hindering solutions despite extensive expert analysis.</p>