Final answer:
The first national crisis faced by President Theodore Roosevelt in 1902 was the coal miners' strike, which led to a significant intervention by the federal government setting a precedent for future labor disputes.
Step-by-step explanation:
Roosevelt's first test of federal power came with the 1902 coal miners' strike. In this significant event, 140,000 coal miners went on strike, putting forth demands for a 20% raise, a 9-hour workday, and the right to organize a union. The situation intensified as coal reserves dwindled after five months with no resolution in sight. Taking unprecedented action, President Roosevelt threatened to nationalize the mines. This led both sides to agree to arbitration, resulting in a compromise settlement that included some concessions to the workers. This event was notable because it demonstrated a new principle that when a strike threatened the public welfare, the federal government was now expected to intervene.
This milestone in labor history encouraged the progressive belief that disputes could be solved with expert intervention, setting a precedent for future governmental involvement in labor disputes.