Air carrier described minimum fuel event due to weather and a reported less than precise ATC plan regarding vectors and probable delays.

Narrative

Forecast showed chance of thunderstorms in vicinity. Captain and crew decided to increase fuel at takeoff to 24K. We got to a high altitude for crossing FL380 vs FL340. Severe thunderstorms and windshear; we got holding and vectors all over the place. We told ATC we cannot take delay. They had no plan! After again stating we cannot take delay; Captain declared minimum fuel. Very poor reaction from ATC. We are east of the airport and are asked to go direct another VOR. We advised ATC we cannot go to that VOR and then to the airport. ATC asks if we are declaring an Emergency? We say if you are insisting on sending us to that VOR we will! We finally get a vector to the south and break out in the clear. We landed with 13.5K. If ATC does not have a plan; they need to get one. Next time we will declare an emergency. The tense situation could have been eliminated by ATC having a plan and telling us what it is. They actually told us; I don't know what their plan is. Due to experienced crewmembers and excellent CRM this event did not become a statistic event