No, it simply does NOT involve "a lot of spending." If you have ever read Art Laffer or the "Supply Side Revolution," you'd realize that supply side has nothing to do with government spending. Reagan wanted to cap government spending, but had a Cold War to fight. But his diaries make clear he opposed that spending. Not one supply-sider I know makes an argument for increased spending, so, your theories are coming out of YOUR keyboard, not out of my head.
Give me ONE major supply side theorist who argues that supply side involves SPENDING.