No. Congressional votes are not inscrutable to the public and one can find any member of congress's entire voting record.
That said, appropriations can from time to time produce "Billion Dollar Hammer" for want of a better term. This occurs when Congress appropriates money for a program that is given a cover term that doesn't describe anything and the only items that are visible in the budget are typical simple tools (i.e. the Hammers or a classified sites' toilets) when they appear in public. Typically these go to an agency (the DOD has a lot of these as the funding usually goes to classified projects or R&D for new weapons tech). However, which department gets what money is still outlined.
It is a War Crime to launch a "surprise" war, and war must formally be declared before any war time engagements can be made. Legally speaking, the U.S. Congress has only declared war five times in the nation's history (The War of 1812, the Mexican-American War, The Spanish-American War, World War I, and World War II)... everything else is authorization of use of military force (AUMF). Typically, these AUMFs will be specific to nations or regions, but the AUMF being used to justify the drone strike is the the AUMF against terrorists, which is pretty broad and allows the President to use military force against "nations, organizations, or persons he determines planned, authorized, committed, or aided the terrorist attacks that occurred on September 11, 2001, or harbored such organizations or persons, in order to prevent any future acts of international terrorism against the United States by such nations, organizations or persons." In addition the AUMF Against Iraq also gives more targeted focus to the nation of Iraq.
Suffice to say "war" was declared.
Additionally, both AUMFs must comply with the War Powers Act requires the President to notify Congress with in 48 hours following the attacks, which he has, and all operations must conclude within 60 days of the initial attack unless an AUMF or declaration of War are passed by Congress. As one person described it to me yesterday, Congress pays for the Sword, while the President swings the Sword. Thus, Congress can always pass a law pulling funding from operations they do not like or sue in the Supreme Court for not following the law.
And keep in mind, the Surprise War Declaration is very important. It's the reason why Pearl Harbor was "a date which will live in Infamy." It was wrong for the Japanese to start the war, but it was more wrong for them to prosecute the war before the Japanese Ambassador to the United States was actually able to decode and give the Japanese Declaration of War on the United States. Japanese leadership was prosecuted for this following the conclusion of World War II and found guilty. What's more, Britain loved this because they could claim the war crime despite the simultaneous attack on British Colonial assets in East Asia and the Pacific. Technically, Japan declared war on Britain on the 8th of December because those attacks lied west of the International Dateline. Because the Declaration was dated to the 7th of December at GMT, even if they were late, they were still "Declaring War before attacking"... it's a loophole but it was one that could be exploited. However, Hawai'i lies East of the Date Line and since the formal Declaration wasn't given to the Secretary of State until well after Pearl Harbor attack was over, the UK could claim that as a War Crime, as they had a Defensive Pact with the United States, which essentially is a fancy way of saying "We consider any act of war against the United States to be an act of War against the United Kingdom" and since Japan didn't declare on either before Pearl Harbor, it technically meant the War on the U.K. was undeclared before the U.K. was engaged).
TL;DR: Declarations of War might ignore time zones of the capital of the defending nation, but the Hostile Nation cannot attack you before they let you know about it... and Japan screwed up in WWII.