You are not smart enough to see it. From post number 262 of this thread, and recently placed;
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Budget Completion or Government Shutdown
If Congress passes, and the president signs, all 12 bills by September 30—the last day of the current fiscal year—the country has a new budget in time for the start of the next fiscal year. If Congress can’t agree on 12 separate bills, it can pass an Omnibus bill with funding for multiple areas. If the budget is not completed by the new fiscal year, Congress must pass a continuing resolution authorizing temporary funding at the previous year’s levels or face a government shutdown.
In the event of a shutdown, the government stops issuing passports, closes national parks and monuments, halts NASA operations, and puts many other functions on hold.
When the budget process is finally complete or Congress passes a continuing resolution, the government resumes normal operations.
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Which was the duress situation Trump faced on his last budget to sign on.
Congress came back with way more spending than he had requested so it was either sign it or shutdown. Damned if he does, damned if he didn't.
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Learn about the federal government’s budget process, from the president’s budget plan to Congress’s work creating funding bills for the president to sign.
www.usa.gov